Subtitles section
Repeat sentence
Subtitles mode
Full screen
Previous
Next
x 1.0
Playback speed
More

Euler line | Special properties and parts of triangles | Geometry | Khan Academy

Video vocabulary

imaginary

Copy vocabulary

US / ɪ'mædʒɪnərɪ /

UK / ɪˈmædʒəˌnɛri /

A2
  • adjecitve
  • Not real; existing only in your imagination

sense

Copy vocabulary

US / sens /

UK / sɛns /

A1
  • noun
  • Certain mental feeling or emotion
  • Normal or clear state of mind
  • Meaning of a particular word, phrase or text
  • verb
  • To perceive using sight, sound, taste touch etc.
  • To recognize the presence of something

but

Copy vocabulary

US / bət /

UK / bʌt,bət /

A1
  • conjunction
  • Used before you say something different, opposite

give

Copy vocabulary

US / ɡɪv /

UK / ɡɪv /

A1
  • noun
  • Degree of flexibility in something, a material
  • verb
  • To hand over or present something to someone
  • To cause someone to have or experience something

good

Copy vocabulary

US / ɡʊd /

UK / ɡʊd /

A1
  • adjecitve
  • Proper, appropriate or right
  • (Of an amount) enough; plenty
  • Excellent; high quality
  • Acting well or properly; of moral character
  • In a positive or happy emotional state
  • noun
  • Advantage or benefit

can

Copy vocabulary

US / kæn /

UK / kən,kæn /

A1
  • noun
  • A metal container for storing food
  • other
  • Able to; have the skill to; have the time to
  • verb
  • To have permission to
  • To be possible to do
  • To preserve food by sealing it in a metal container

enter

Copy vocabulary

US / 'entə(r) /

UK / ˈɛntɚ /

A1
  • verb
  • To start a career or an education
  • To become a competitor in a contest
  • To add or type information in a computer
  • To go into a room, building etc.

angle

Copy vocabulary

US / ˈæŋgl /

UK / ˈæŋɡəl /

B1
  • noun
  • Place where two lines or surfaces meet

equal

Copy vocabulary

US / 'i:kwəl /

UK / ˈikwəl /

A1
  • adjecitve
  • Same in shape, size, or number
  • verb
  • To add up or be the same as

now

Copy vocabulary

US / naʊ /

UK / naʊ /

A1
  • adverb
  • At the present time or moment
  • Right away or in the next possible moment
  • Used to refer to something that just happened
  • Time between the present and a moment in the past
  • conjunction
  • Resulting from or because of something

neat

Copy vocabulary

US / ni:t /

UK / nit /

A2
  • adjecitve
  • That you approve of; cool
  • (Of alcohol) not weakened with water or a mixer
  • Not messy; clean and orderly; simple and effective

crazy

Copy vocabulary

US / 'kreɪzɪ /

UK / ˈkrezi /

A2
  • adjecitve
  • Mentally ill; mad
  • Not being sensible or practical
  • Really like someone or something very much
  • noun
  • Person acting in a manner that is strange and odd

vertex

Copy vocabulary

US / ˈvɜ:teks /

UK / ˈvɜ:rteks /

A1
  • noun
  • Summit; highest point; pl; vertices

video

Copy vocabulary

US / 'vɪdɪəʊ /

UK / ˈvɪdiˌo /

A2
  • adjecitve
  • Of a moving film, with sound
  • noun
  • Recording capturing action with sound
  • verb
  • To make a moving film of, with sound

maybe

Copy vocabulary

US / ˈmeɪbi /

UK / ˈmebi /

A1
  • adverb
  • Possibly but not certainly; perhaps

not

Copy vocabulary

US / nɒt /

UK / nɑt /

A1
  • adverb
  • Word indicating the negative
  • (Used to form the negative of verbs)

our

Copy vocabulary

US / 'aʊə(r) /

UK / aʊr /

A1
  • determiner
  • Belonging to us

whole

Copy vocabulary

US / həul /

UK / hol /

A1
  • adjecitve
  • Complete or full; all of
  • Being in a good condition
  • noun
  • Complete amount or sum; total

become

Copy vocabulary

US / bɪ'kʌm /

UK / bɪˈkʌm /

A1
  • verb
  • To begin to be; grow to be; develop into
  • To be suitable for a particular job or role

same

Copy vocabulary

US / seɪm /

UK / sem /

A1
  • adjecitve
  • Being equal in quality and amount
  • Identical; not different
  • Not changing; constant

really

Copy vocabulary

US / ˈri:əli /

UK / ˈriəˌli, ˈrili /

A1
  • adverb
  • Used to stress something that is said; definitely
  • In a true or accurate manner
  • Very

would

Copy vocabulary

US / wʊd /

UK / wʊd /

A1
  • other
  • Used to indicate something imagined
  • Used to ask or request something politely
  • Verb used to indicate possibility, request etc.
  • Used to indicate a preference
  • Used to indicate a reaction
  • Indicates something that occurred repeatedly
  • Used to indicate willingness or ability to do

let

Copy vocabulary

US / let /

UK / lɛt /

A1
  • verb
  • To allow someone to do something
  • Introducing a suggestion to do something together
  • To rent a house, etc. to others

little

Copy vocabulary

US / 'lɪtl /

UK / ˈlɪtl /

A1
  • adjecitve
  • Being short in length of time
  • Not great in size, amount, or degree; small
  • Being very young or younger than others
  • adverb
  • By an amount or degree that is not very much
  • Not often; rarely
  • noun
  • A person's name

the

Copy vocabulary

US / ðə /

UK / ðə /

A1
  • article
  • Used to refer to something already mentioned
  • Used to show there is only one of something
  • determiner
  • Used to describe all of a family

exponential

Copy vocabulary

US / ˌekspəˈnenʃl /

UK / ˌɛkspəˈnɛnʃəl /

C1
  • adjecitve
  • (Of an increase) at a faster and faster rate

make

Copy vocabulary

US / meɪk /

UK / mek /

A1
  • noun
  • Product made by a particular company; brand
  • verb
  • To arrange or prepare something e.g. dinner
  • To get to (a place) on time
  • To gain the status of (teacher, lawyer, etc.)
  • To create something by putting things together
  • To earn a certain amount of money at a job
  • To cause or force a person to do something
  • To cause something to happen or be formed

famous

Copy vocabulary

US / 'feɪməs /

UK / ˈfeməs /

A1
  • adjecitve
  • Excellent
  • Widely known; recognized by many people

other

Copy vocabulary

US / 'ʌðə(r) /

UK / ˈʌðər /

A1
  • adjecitve
  • A thing different from that mentioned
  • determiner
  • (Something) else; not the first (one)
  • pronoun
  • Being the one and only thing of that category

neatly

Copy vocabulary

US / ni:tlɪ /

UK / ˈnitlɪ /

A2
  • adverb
  • With neatness

one

Copy vocabulary

US / wʌn /

UK / wʌn /

A1
  • pronoun
  • You; we; people in general; someone
  • The thing or person previously referred to
  • adjecitve
  • Used to refer to people generally
  • Being a strong example of (something mentioned)
  • number
  • Number 1

than

Copy vocabulary

US / ðən /

UK / ðən /

A1
  • conjunction
  • Used to compare two things that are not equal

also

Copy vocabulary

US / 'ɔ:lsəʊ /

UK / ˈɔlso /

A1
  • adverb
  • In addition; too; in a similar way

attempt

Copy vocabulary

US / ə'tempt /

UK / əˈtɛmpt /

A2
  • noun
  • Effort made to try to do or accomplish something
  • verb
  • To try to do something challenging or difficult

kind

Copy vocabulary

US / kaɪnd /

UK / kaɪnd /

A1
  • adjecitve
  • In a caring and helpful manner
  • friendly and considerate
  • noun
  • One type of thing

you

Copy vocabulary

US / jʊ /

UK / ju /

A1
  • pronoun
  • Person someone is speaking or writing to
  • Person or people in general

centroid

Copy vocabulary

US / ˈsentrɔɪd /

UK / ˈsentrɔɪd /

A1
  • noun
  • Center of mass of an object of uniform density

opposite

Copy vocabulary

US / ˈɔpəzit /

UK / ˈɑpəzɪt /

A2
  • adjecitve
  • Being totally different from
  • noun
  • Person, thing that is totally different to another
  • preposition
  • Across from or on the side facing something

free

Copy vocabulary

US / fri: /

UK / fri /

A1
  • adjecitve
  • Living, happening without being controlled
  • Costing no money
  • Not working; not busy
  • verb
  • To release (e.g. bird) from a cage or prison

this

Copy vocabulary

US / ðɪs /

UK / ðɪs /

A1
  • adjecitve
  • Used to indicate something already been discussed
  • Used to indicate something happening around now
  • adverb
  • An indication by a physical motion or gesture
  • A specific amount of
  • determiner
  • Person, thing, or idea near you
  • pronoun
  • Person, thing that has already been discussed

although

Copy vocabulary

US / ɔ:lˈðəu /

UK / ɔlˈðo /

A1
  • conjunction
  • Despite the fact that; however

multiple

Copy vocabulary

US / ˈmʌltɪpl /

UK / ˈmʌltəpəl /

B1
  • adjecitve
  • Having or involving more than one of something
  • noun
  • Number produced by multiplying a smaller number
  • Shop with many branches

three

Copy vocabulary

US / θri: /

UK / θri /

A1
  • number
  • Number 3

cool

Copy vocabulary

US / ku:l /

UK / kul /

A1
  • adjecitve
  • Steady and calm when facing difficulties
  • Almost cold; not warm or hot
  • Smart or stylish in a way (young) people admire
  • Unfriendly in an indirect way; distant
  • verb
  • To make something decrease in temperature
  • (Of an emotion, etc.) to become less strongly felt

definitely

Copy vocabulary

US / ˈdefɪnətli /

UK / ˈdefɪnətli /

A2
  • adverb
  • Without question; beyond doubt

define

Copy vocabulary

US / dɪ'faɪn /

UK / dɪˈfaɪn /

A2
  • verb
  • To explain the meaning of words
  • To set or mark the limits of something

just

Copy vocabulary

US / dʒʌst /

UK / dʒʌst /

A1
  • adjecitve
  • Proper or appropriate; as is deserved
  • Doing or being what is right or fair
  • Legally correct; having enough evidence
  • adverb
  • Almost; nearly
  • Exactly at the time of
  • Exactly (the same as, like)

line

Copy vocabulary

US / laɪn /

UK / laɪn /

A1
  • noun
  • Border that divides two places or regions
  • Long crease in the skin, often from age
  • Mark that is long, straight and very thin
  • Row of words, letters or numbers that are written
  • Telephone connection
  • People waiting one behind the other; queue
  • Long thin wire, e.g. for electrical signal
  • verb
  • To put material along the inside of something

few

Copy vocabulary

US / fju: /

UK / fju /

A1
  • pronoun
  • Not many, a small number

perpendicular

Copy vocabulary

US / ˌpɜ:pənˈdɪkjələ(r) /

UK / ˌpə:pənˈdɪkjəlɚ /

C1
  • adjecitve
  • Being at right angles to a given line or plane

responsible

Copy vocabulary

US / rɪ'spɒnsəbl /

UK / rɪˈspɑnsəbəl /

A2
  • adjecitve
  • Being the cause of something that has occurred
  • Having the duty of dealing with something
  • Able to be trusted to do what needs to be done

start

Copy vocabulary

US / stɑ:t /

UK / stɑrt /

A1
  • noun
  • First time or place that a thing exists; beginning
  • First opportunity to achieve something, e.g. a job
  • Sudden action or movement because you are scared
  • other
  • Beginning of something in place or time
  • verb
  • To do, be or happen for the first time; begin
  • To turn something on

unique

Copy vocabulary

US / jʊ'ni:k /

UK / juˈnik /

A2
  • adjecitve
  • Unlike other things; being the only one like it

well

Copy vocabulary

US / wel /

UK / wɛl /

A1
  • adjecitve
  • Being in a fortunate, good condition or state
  • Healthy and in good condition
  • adverb
  • In an acceptable, proper, or successful manner
  • In a complete, total, or full manner
  • A great and considerable degree
  • In a successful way, in a good or satisfactory way
  • exclamation
  • Used to begin or continue a particular statement
  • Used to show you want to start saying something
  • Used to express that you are waiting for a reply
  • You say this to change the topic of a conversation
  • Used to indicate you are making a final remark
  • noun
  • Long deep hole in the ground to get water
  • verb
  • To cause your eyes to fill with tears

compound

Copy vocabulary

US / 'kɒmpaʊnd /

UK / kɑmˈpaUnd /

B1
  • adjecitve
  • (Of a term) created by combining two or more words
  • noun
  • Series of buildings that are walled or fenced off
  • Chemical made up of several others
  • Closed walled area, as in a prison
  • Something formed by combining elements/parts
  • Term created by using two or more words together
  • verb
  • To pay interest on a loan including the interest
  • To make something from various parts or components
  • To make a mistake or problem worse

for

Copy vocabulary

US / fə(r) /

UK / fɔr,fə /

A1
  • preposition
  • Used to show the purpose, or need of something

necessarily

Copy vocabulary

US / ˌnesəˈserəli /

UK / ˌnɛsɪˈsɛrəli, -ˈsɛr- /

A2
  • adverb
  • In a way that is needed/required/is unavoidable

why

Copy vocabulary

US / waɪ /

UK / hwaɪ, waɪ /

A1
  • adverb
  • Question word to ask for a reason
  • exclamation
  • (Used to express surprise or approval)

anyway

Copy vocabulary

US / ˈeniweɪ /

UK / ˈɛniˌwe /

A1
  • adverb
  • A word used to change the topic of a conversation

special

Copy vocabulary

US / 'speʃl /

UK / ˈspɛʃəl /

A1
  • adjecitve
  • Being additional or extra
  • Different, better or greater than normal
  • noun
  • Heavily discounted sales item

any

Copy vocabulary

US / 'enɪ /

UK / ˈɛni /

A1
  • adjecitve
  • One, or some, no matter which
  • pronoun
  • One (thing) of many; some

come

Copy vocabulary

US / kʌm /

UK / kʌm /

A1
  • verb
  • To arrive at a place
  • (Of mail) to be delivered
  • To move toward someone; go with someone
  • To reach a certain point or state

completely

Copy vocabulary

US / kəmˈpli:tli /

UK / kəmˈpliːtli /

A1
  • adverb
  • In every way or as much as possible

clean

Copy vocabulary

US / kli:n /

UK / klin /

A1
  • adjecitve
  • Not marked in any way; blank
  • Done according to the rules or standards; fair
  • Free from disease or sickness
  • Being free from dirt or marks; washed
  • Behaving well; not breaking any rules; legal
  • adverb
  • Completely; entirely
  • verb
  • To make free from dirt or marks; washed
  • To make neat and orderly e.g. a room
  • To remove the inner parts of an animal

nine

Copy vocabulary

US / naɪn /

UK / naɪn /

A1
  • number
  • 9

only

Copy vocabulary

US / ˈəunli /

UK / ˈonli /

A1
  • adverb
  • Just one; just that amount or thing; not more than
  • Not very important or serious
  • Just that type of thing, person
  • Short time ago; not before a certain time
  • conjunction
  • Except; but

two

Copy vocabulary

US / tu: /

UK / tu /

A1
  • number
  • 2

most

Copy vocabulary

US / məʊst /

UK / most /

A1
  • adverb
  • Very; extremely
  • Greatest possible degree
  • pronoun
  • Nearly all of something

and

Copy vocabulary

US / ənd /

UK / ənd, ən,ænd /

A1
  • conjunction
  • Used to refer to two or more things
  • Plus; in addition; on top of that
  • Used to introduce an action that follows another

hopefully

Copy vocabulary

US / ˈhəʊpfəli /

UK / ˈhopfəli /

A2
  • adverb
  • In a manner wishing something to happen

guy

Copy vocabulary

US / ɡaɪ /

UK / ɡaɪ /

A1
  • noun
  • Man; boy; any person

lot

Copy vocabulary

US / lɒt /

UK / lɑt /

A1
  • noun
  • What happens to a person in life from chance; fate
  • A group of people seen together
  • Item for sale at an auction
  • Small area of land used for a purpose e.g. parking

call

Copy vocabulary

US / kɔ:l /

UK / kɔl /

A1
  • noun
  • A order or request for action
  • The sound an animal makes, often when in danger
  • A correct prediction, e.g. a decision in a game
  • A short visit to a place or person
  • A decision by a referee or umpire in a game
  • verb
  • To make a request or order for action
  • (Animal) to make sounds to warn of danger
  • To announce the date of an election
  • To make a judgment about something
  • To give someone or something a name
  • To guess in advance the result or outcome
  • To visit a place or person for a short time
  • To phone someone
  • To speak, announce or shout in a loud voice

mathematician

Copy vocabulary

US / ˌmæθəməˈtɪʃn /

UK / ˌmæθəməˈtɪʃən /

A2
  • noun
  • Student of or teacher of mathematics

tight

Copy vocabulary

US / taɪt /

UK / taɪt /

A2
  • adjecitve
  • Showing anxiety or anger; tense
  • Positioned physically close together
  • Managed or controlled in a strict and careful way
  • (Of road, bend) curving sharply
  • Drunk
  • Being equally matched in ability or score
  • Lacking extra space
  • Having limited time available
  • Being very limited in supply
  • Not generous; mean with money; stingy
  • (Rope or tie) pulled strongly
  • Being in a good solid relationship
  • adverb
  • Firmly; so it can't move

another

Copy vocabulary

US / əˈnʌðə(r) /

UK / əˈnʌðɚ /

A1
  • adjecitve
  • One more, but not this
  • determiner
  • One more added
  • pronoun
  • One more (thing)

from

Copy vocabulary

US / frəm /

UK / frʌm, frɑm,frəm /

A1
  • preposition
  • Starting at a particular place, time or level

median

Copy vocabulary

US / ˈmi:diən /

UK / ˈmidiən /

B2
  • adjecitve
  • Being in the middle or average
  • noun
  • Middle of an ordered set of numbers

out

Copy vocabulary

US / aʊt /

UK / aʊt /

A1
  • adverb
  • No longer stylish (e.g. fashion)
  • Away from home, business, or the usual place
  • In a direction/movement away from inside or center
  • noun
  • Act when a batter cannot continue playing
  • verb
  • To tell people a secret

over

Copy vocabulary

US / 'əʊvə(r) /

UK / ˈovɚ /

A1
  • adverb
  • Finished; no longer happening
  • Towards the ground/away from a standing position
  • noun
  • A set of six consecutive balls bowled in cricket
  • other
  • Finished
  • preposition
  • Showing the relation when a thing is above another
  • On or covering something
  • Above or across something
  • More than you need
  • From one side to the other
  • In the direction of; toward

name

Copy vocabulary

US / neɪm /

UK / nem /

A1
  • noun
  • What something or someone is called
  • verb
  • To state what someone is called, e.g. John

something

Copy vocabulary

US / ˈsʌmθɪŋ /

UK / ˈsʌmθɪŋ /

A1
  • adverb
  • In some degree or measure
  • noun
  • a person or thing of some value or consequence
  • pronoun
  • Thing that is not yet known or named
  • Approximately

first

Copy vocabulary

US / fɜ:st /

UK / fɚst /

A1
  • adjecitve
  • 1st; Coming before all others in time or place
  • noun
  • Something that has not happened before
  • Position of the winner of a competition

get

Copy vocabulary

US / ɡet /

UK / ɡɛt /

A1
  • verb
  • To become affected by illness or disease
  • To begin to feel or understand an emotion or idea
  • To send or bring someone or something home, etc.
  • To go somewhere to obtain something
  • To (cause to) do a particular thing
  • To obtain, receive or be given something
  • To currently have
  • To prepare for use
  • To understand something being said or read

roughly

Copy vocabulary

US / ˈrʌfli /

UK / ˈrʌflɪ /

B1
  • adverb
  • Approximately; (of numbers) about; around
  • In a manner that is violent or not careful
  • In an inexact, imprecise or violent way
  • In a basic, simple manner

bizarre

Copy vocabulary

US / bɪˈzɑ:(r) /

UK / bɪˈzɑr /

B2
  • adjecitve
  • Odd or strange

each

Copy vocabulary

US / i:tʃ /

UK / itʃ /

A1
  • determiner
  • Every one of two or more things
  • pronoun
  • Per one person or thing

triangle

Copy vocabulary

US / ˈtraɪæŋgl /

UK / ˈtraɪˌæŋɡəl /

B1
  • noun
  • Three people connected with each in a relationship
  • A three-sided piece of metal used in orchestras
  • A closed shape with three straight sides

growth

Copy vocabulary

US / grəʊθ /

UK / groʊθ /

A2
  • noun
  • Improvement, development in a skill over time
  • A mass on the skin or body part related to illness
  • Act of growing

right

Copy vocabulary

US / raɪt /

UK / raɪt /

A1
  • adjecitve
  • Correct or true
  • The south side of you looking at the rising sun
  • adverb
  • Exactly in a place or time
  • Being appropriate for a particular event
  • In a straight or direct manner
  • noun
  • Something you are legally or morally allowed to do
  • Ideal of what is just and good
  • Political view based on conservatism
  • verb
  • To fix something previously wrong or unjust
  • To make upright, as a boat that has turned over

interesting

Copy vocabulary

US / ˈɪntrəstɪŋ /

UK / ˈɪntrɪstɪŋ, -tərɪstɪŋ, -təˌrɛstɪŋ /

A1
  • adjecitve
  • Taking your attention; making you want to know
  • verb
  • To make someone want to know about something
  • To persuade to do, become involved with something

nothing

Copy vocabulary

US / 'nʌθɪŋ /

UK / ˈnʌθɪŋ /

A1
  • noun
  • Item of little or no value, importance, interest
  • Number or value of zero
  • pronoun
  • Not anything, not a single thing

number

Copy vocabulary

US / ˈnʌmbə(r) /

UK / ˈnʌmbɚ /

A1
  • noun
  • Symbols such as 1, 2, 56, 793
  • Particular song or dance performed during a show
  • Total quantity or amount of things
  • verb
  • To put numbers on things
  • To assign a sequence within a group, series, set
  • To claim to be part of a larger group, series, set

square

Copy vocabulary

US / skweə(r) /

UK / skwɛr /

A2
  • adjecitve
  • Being fair or honest
  • Multiply a number by itself e.g. 2x2 or 6x6
  • noun
  • Shape with 4 equal length sides and 4 equal angles
  • The result of multiplying Length by the width
  • Open public area in the middle of the town
  • verb
  • To make something balance or be equal
  • To multiply a number by itself, e.g. 2x2 or 6x8
  • To straighten the edge to form a four-sided shape

tell

Copy vocabulary

US / tel /

UK / tɛl /

A1
  • verb
  • To (strongly) advise a person to do something
  • To be able to guess
  • To say or communicate information to someone
  • To inform, but without speaking; indicate
  • To have a negative effect on someone
  • To order someone to do something; command
  • To recognize something based on certain signs
  • To report something to an authority
  • To explain something or teach someone something

down

Copy vocabulary

US / daʊn /

UK / daʊn /

A1
  • adjecitve
  • Being sad, sick, or unhappy
  • Not operating, working, or functioning as expected
  • adverb
  • In a sitting or lying position
  • Towards or on the ground, floor, or bottom
  • Written or copied onto a piece of paper or book
  • noun
  • A period of play in American Football
  • The soft, smooth hairs that cover a bird's body
  • preposition
  • Along something's path, course, or direction
  • Going from a higher position to a lower position
  • verb
  • To eat or drink very quickly and without stopping

frankly

Copy vocabulary

US / ˈfræŋkli /

UK / ˈfræŋkli /

B2
  • adverb
  • Speaking honestly and directly

then

Copy vocabulary

US / ðen /

UK / ðɛn /

A1
  • adverb
  • A time that is not now
  • Following another thing in time or arrangement
  • Following on reasonably from what was just stated
  • At that time, not now

again

Copy vocabulary

US / ə'ɡen /

UK / əˈɡɛn /

A1
  • adverb
  • One more time, once more

about

Copy vocabulary

US / ə'baʊt /

UK / əˈbaʊt /

A1
  • adverb
  • To be ready to; going to
  • Nearly; approximately; roughly
  • Near; next to; close to
  • In every direction; in the area of
  • preposition
  • Concerning or of (a topic)

different

Copy vocabulary

US / ˈdɪfrənt /

UK / ˈdɪfrənt /

A1
  • adjecitve
  • Not of the same kind; unlike other things

eyeball

Copy vocabulary

US / ˈaɪbɔ:l /

UK / ˈaɪˌbɔl /

C2
  • noun
  • The round part of the eye

even

Copy vocabulary

US / 'i:vn /

UK / ˈivən /

A1
  • adjecitve
  • Being equal in influence, power, possibility etc.
  • Being divided equally or fairly
  • (Of teams/contest) with similar chances of success
  • Smooth, level, or regular
  • Can be divided by 2; ending in 2, 4, 6, 8, or 0
  • At a regular, equally steady manner
  • Remaining steady and unchanging
  • adverb
  • (When this is surprising) as well; too
  • (Used to compare two things/stress the difference)
  • verb
  • To make something level; to flatten
  • To make something equal

label

Copy vocabulary

US / 'leɪbl /

UK / ˈlebəl /

A2
  • noun
  • A (luxury) brand owned by a company
  • A word or term used to describe a person, thing
  • A piece of paper or material to identify something
  • verb
  • To use a term to describe, often negatively
  • To attach material to identify something

like

Copy vocabulary

US / laɪk /

UK / laɪk /

A1
  • adjecitve
  • Being equal in status or kind to something else
  • Similar; the same
  • adverb
  • For example
  • preposition
  • Used as a filler; used to ad emphasis
  • In a way similar to the way something is done
  • Such as; for example
  • verb
  • To want to
  • To find something pleasing; to prefer something

sit

Copy vocabulary

US / sɪt /

UK / sɪt /

A1
  • verb
  • To take an exam
  • To be in a resting position on a chair
  • To provide seating for people
  • To remain in a still position while being painted

what

Copy vocabulary

US / wɒt /

UK / hwɑt, hwʌt, wɔt, wʌt,hwət, wət /

A1
  • pronoun
  • Thing or things that; the same kind as
  • Used to emphasize something you are about to say
  • adjecitve
  • Used to refer to a particular amount, or number
  • Used to place emphasis on a particular quality
  • adverb
  • To a certain degree
  • determiner
  • Question words used for asking for information
  • exclamation
  • Used to express excitement, shock, or surprise
  • Used to ask people to repeat something they said

that

Copy vocabulary

US / ðæt /

UK / ðæt, ðət /

A1
  • adjecitve
  • The person or thing being talked about
  • Used to identify something both the speakers know
  • adverb
  • Used to reinforce adjectives and adverbs
  • To such a degree
  • conjunction
  • Used to connect a noun clause
  • Used to introduce an adverbial clause
  • Used to introduce a noun clause
  • determiner
  • Used as a noun to refer to something
  • pronoun
  • Referring an object far away
  • Used to refer to the relative pronoun ‘which’

find

Copy vocabulary

US / faɪnd /

UK / faɪnd /

A1
  • noun
  • Object discovered by chance
  • Things that have been discovered from searching
  • verb
  • To become aware of something that is happening
  • To discover or meet by chance
  • To decide if someone is guilty of a crime, or not
  • To learn through study, research, or effort
  • To discover something by looking for it

enough

Copy vocabulary

US / ɪˈnʌf /

UK / ɪˈnʌf /

A1
  • adjecitve
  • Sufficient to answer the need
  • adverb
  • To a satisfactory degree
  • pronoun
  • Equal to what is needed; as much as required
  • Adequate number or amount

mystical

Copy vocabulary

US / ˈmɪstɪkl /

UK / ˈmɪstɪkəl /

B2
  • adjecitve
  • Awe-inspiring or mysterious

tend

Copy vocabulary

US / tend /

UK / tɛnd /

A2
  • verb
  • To move or act in a certain manner
  • To take care of
  • To regularly behave in a certain way

intersect

Copy vocabulary

US / ˌɪntə'sekt /

UK / ˌɪntɚˈsɛkt /

B2
  • verb
  • To divide something by crossing it

reason

Copy vocabulary

US / 'ri:zn /

UK / ˈrizən /

A1
  • noun
  • Ability to think about facts and form a judgment
  • Explanation for why something occurred or was done
  • verb
  • To think and make conclusions in a logical manner

side

Copy vocabulary

US / saɪd /

UK / saɪd /

A1
  • adjecitve
  • In addition to the central or most important thing
  • Next to, or very close to, the right or left of
  • noun
  • Position or opinion that is opposite to another
  • Right or left part of a person's body
  • Feature of someone's personality
  • Straight edge of an object
  • One of two or more groups fighting each other
  • verb
  • To decide to agree with one point, not the other

altitude

Copy vocabulary

US / 'æltɪtju:d /

UK / ˈæltɪˌtud,-ˌtjud /

B2
  • noun
  • Height of something above sea level

imagine

Copy vocabulary

US / ɪ'mædʒɪn /

UK / ɪˈmædʒɪn /

A1
  • verb
  • To think creatively about; form mental picture of

four

Copy vocabulary

US / fɔ:(r) /

UK / fɔr, for /

A1
  • number
  • 4

geometry

Copy vocabulary

US / dʒiˈɒmətri /

UK / dʒiˈɑ:mətri /

B2
  • noun
  • Mathematical study of shapes, surfaces, and space
  • Mathematical shape of something

once

Copy vocabulary

US / wʌns /

UK / wʌns /

A1
  • adverb
  • One time; one instance
  • At a time in the past
  • conjunction
  • When; as soon as

obviously

Copy vocabulary

US / ˈɒbviəsli /

UK / ˈɑːbviəsli /

A2
  • adverb
  • In a way that is obvious/easy to see or understand

reality

Copy vocabulary

US / rɪ'ælətɪ /

UK / riˈælɪti /

A2
  • noun
  • What is true, as opposed to what is imagined

straight

Copy vocabulary

US / streɪt /

UK / stret /

A2
  • adjecitve
  • Not having curves, bends, or angles
  • Not gay; heterosexual
  • honest and direct
  • adverb
  • in a line; immediately; honestly and directly

weird

Copy vocabulary

US / wɪəd /

UK / wɪrd /

B1
  • adjecitve
  • Odd or unusual; surprising; strange

point

Copy vocabulary

US / pɔɪnt /

UK / pɔɪnt /

A1
  • noun
  • An item to be discussed
  • Small spot or dot
  • Fact or detail
  • Feature of something
  • The size of the text on a page or screen
  • A certain time or stage in a process
  • Certain position in time or space
  • Idea or fact you try to convince people about
  • Measurement of scores in a game, sport
  • Sharp end of something, e.g. a pen or pin
  • verb
  • To face a certain direction, e.g. north
  • To indicate something with your finger to others

after

Copy vocabulary

US / 'ɑ:ftə(r) /

UK / ˈæftɚ /

A1
  • adverb
  • Later than another time, or behind something
  • conjunction
  • Following something before
  • preposition
  • When an event happened or time has passed

already

Copy vocabulary

US / ɔ:lˈredi /

UK / ɔlˈrɛdi /

A1
  • adverb
  • Having happened or been done before this time

guess

Copy vocabulary

US / ɡes /

UK / ɡɛs /

A1
  • noun
  • Answer given when you don't know if it is correct
  • verb
  • To give an answer without knowing if it is correct

itself

Copy vocabulary

US / ɪtˈself /

UK / ɪtˈsɛlf /

A1
  • pronoun
  • Referring to it

will

Copy vocabulary

US / wɪl /

UK / wɪl /

A1
  • noun
  • Desire or choice of someone
  • Document saying who gets your money when you die
  • Strong desire to do something; determination
  • Desire to do something; strong wish to do
  • other
  • Used with verbs to express the future
  • verb
  • To leave property to someone after your death
  • To use mental effort to make something happen
  • Am (is, are) likely to do
  • To influence someone to do something
  • To make something happen by strongly wanting it

here

Copy vocabulary

US / hɪə(r) /

UK / hɪr /

A1
  • adverb
  • In this place; at this location, position or time

new

Copy vocabulary

US / nju: /

UK / nu, nju /

A1
  • adjecitve
  • Not old, recently born, built or made
  • Being or doing something for the first time
  • Not felt, seen or known previously
  • Having been recently bought or obtained

try

Copy vocabulary

US / traɪ /

UK / traɪ /

A1
  • noun
  • Act of putting the ball over the rugby goal line
  • verb
  • To make an effort, to attempt to do something
  • To examine someone or something in a court of law
  • To test to see if it is good or you like it
  • To make a person go through hardship; test
  • To examine something to see if it works

actually

Copy vocabulary

US / ˈæktʃuəli /

UK / ˈæktʃuəli /

A1
  • adverb
  • Used to add new (often different) information

write

Copy vocabulary

US / raɪt /

UK / raɪt /

A1
  • verb
  • To compose letters and words on paper or a screen
  • To invent or create a computer program
  • To create a song or piece of music

draw

Copy vocabulary

US / drɔ: /

UK / drɔ /

A1
  • noun
  • Something that attracts people to visit a place
  • A lottery or prize
  • Result of a game, contest where the score is equal
  • verb
  • To attract attention to someone or something
  • To get closer to or approach something or someone
  • To influence a person's involvement in something
  • To move an object by pulling
  • To create an image using pen or pencil and paper
  • To take one thing out of a container, etc.
  • (Of 2 teams) to finish a game with the same score

unlikely

Copy vocabulary

US / ʌnˈlaɪkli /

UK / ʌnˈlaɪkli /

A2
  • adjecitve
  • Not seeming suitable for a particular purpose
  • adverb
  • Not likely to happen; not likely to be the truth

center

Copy vocabulary

US / 'sentə /

UK / ˈsɛntɚ /

A1
  • noun
  • Community place people go health or social reasons
  • Place in the middle of something
  • Person or thing that is attracting attention
  • verb
  • To direct focus toward something

exist

Copy vocabulary

US / ɪɡ'zɪst /

UK / ɪɡˈzɪst /

A1
  • verb
  • To be present, alive or real

explore

Copy vocabulary

US / ɪk'splɔ:(r) /

UK / ɪkˈsplɔr /

A2
  • verb
  • To examine something in detail to learn about it
  • To travel to a place to discover more about it

interest

Copy vocabulary

US / 'ɪntrəst /

UK / ˈɪntrɪst, -tərɪst, -ˌtrɛst /

A1
  • noun
  • Best or most advantageous thing for someone
  • Activity or subject one enjoys doing or learning
  • Fee for borrowing money
  • verb
  • To make someone want to know about something
  • To persuade to do, become involved with something

remember

Copy vocabulary

US / rɪ'membə(r) /

UK / rɪˈmɛmbɚ /

A1
  • verb
  • To give someone a gift, e.g. birthday, wedding
  • To hold a thought in your mind to not forget it
  • To bring a previous image or idea to your mind

ratio

Copy vocabulary

US / ˈreɪʃiəʊ /

UK / ˈreɪʃioʊ /

C2
  • noun
  • The relationship in relative size, etc.

know

Copy vocabulary

US / nəʊ /

UK / noʊ /

A1
  • verb
  • To be familiar with a person or place, thing
  • To feel sure or be convinced about something
  • To discover or be aware of something
  • To be able to distinguish
  • To have knowledge of things

with

Copy vocabulary

US / wɪð /

UK / wɪð, wɪθ /

A1
  • preposition
  • As an employee of a certain company
  • Against something or someone
  • By using something as a means
  • Due to; because of
  • Including
  • Possessing as a feature
  • Related to
  • (Of the manner/attitude by which you do something)
  • Used to express that people or things are together

diameter

Copy vocabulary

US / daɪˈæmɪtə(r) /

UK / daɪˈæmɪtɚ /

B1
  • noun
  • Distance across the center of an object

mathematical

Copy vocabulary

US / ˌmæθə'mætɪkl /

UK / ˌmæθəˈmætɪkəl /

A2
  • adjecitve
  • Concerning numbers and equations

negative

Copy vocabulary

US / 'neɡətɪv /

UK / ˈnɛɡətɪv /

A2
  • adjecitve
  • Being harmful, unwanted or unhelpful
  • In mathematics, being less than zero
  • Focusing on the bad aspects; pessimistic
  • noun
  • The opposite to a positive electrical charge
  • In grammar, containing words such as 'no' or 'not'
  • Reply to a question or statement that means 'no'
  • Image on camera film used to make a photo

see

Copy vocabulary

US / si: /

UK / si /

A1
  • verb
  • To go on a date with someone
  • To predict whether something is, or will be true
  • To understand what someone says
  • To use your eyes to look at something
  • To visit a place often for sightseeing or pleasure
  • To visit or meet with someone
  • To find out by waiting or looking
  • To watch (a game, movie or TV show)

circumference

Copy vocabulary

US / səˈkʌmfərəns /

UK / sərˈkʌmfərəns /

C1
  • noun
  • Length around an outer boundary, e.g. a circle

equilateral

Copy vocabulary

US / ˌi:kwɪ'lætərəl /

UK / ˌikwəˈlætərəl, ˌɛkwə- /

C2
  • noun
  • Math figure whose sides are all equal

have

Copy vocabulary

US / həv /

UK / hæv /

A1
  • verb
  • To drink, smoke, eat or use something
  • To experience the effects of something
  • To organize an event, or join in an activity
  • To own, possess, or hold something
  • To cause to happen or produce a particular effect

midpoint

Copy vocabulary

US / 'mɪdpɔɪnt /

UK / ˈmɪdˌpɔɪnt /

B1
  • noun
  • Point in or at the middle of something

playlist

Copy vocabulary

US / ˈpleɪlɪst /

UK / ˈpleɪlɪst /

A1
  • noun
  • List of musical selections to be performed

ruler

Copy vocabulary

US / ˈru:lə(r) /

UK / ˈrulɚ /

A1
  • noun
  • Someone who has control over a country or area
  • Straight instrument used for measuring things

world

Copy vocabulary

US / wɜ:ld /

UK / wɜrld /

A1
  • noun
  • All the humans, events, activities on the earth
  • Political division due to some kind of similarity

all

Copy vocabulary

US / ɔ:l /

UK / ɔl /

A1
  • adverb
  • Completely; totally
  • determiner
  • Being every one of something
  • pronoun
  • 100% of something; the complete amount

drop

Copy vocabulary

US / drɒp /

UK / drɑp /

A1
  • noun
  • Distance between a higher and a lower level
  • Act of letting something fall (from your hand)
  • A decrease in quantity or quality; reduction
  • Tiny amount of liquid, with rounded bottom
  • verb
  • To drive someone to a place and then drive away
  • To let something fall from your hand
  • To fall or lie down quickly, as when shot
  • To decide to stop something e.g. a course)
  • To (cause to) reduce in quantity or quality

its

Copy vocabulary

US / ɪts /

UK / ɪts /

A1
  • adjecitve
  • Referring to or belonging to ‘it’
  • determiner
  • Of something; belonging or related to something
  • other
  • Possessive form of “it”

who

Copy vocabulary

US / hu: /

UK / hu /

A1
  • pronoun
  • Which person
  • Used to introduce information about people

take

Copy vocabulary

US / teɪk /

UK / tek /

A1
  • noun
  • Filming of a single scene for TV or the movies
  • verb
  • To accept something that is offered
  • To use a method of traveling, e.g. a bus or train
  • To use a camera to make (a photo)
  • To pick up something and go away with it
  • To study a subject in school
  • To attempt to pass (an exam)
  • To require a certain amount of time, money, space

identity

Copy vocabulary

US / aɪ'dentətɪ /

UK / aɪˈdɛntɪti /

B1
  • noun
  • Collection of qualities that makes a person

show

Copy vocabulary

US / ʃəʊ /

UK / ʃo /

A1
  • noun
  • False display of love, emotion or action
  • An event for displaying or promoting goods
  • Play, opera or theater production
  • Presentation that is broadcast on TV or radio
  • verb
  • To be easily seen or displayed
  • To display your emotions or feelings
  • To let someone see something; display
  • To explain or teach how something is done
  • To lead someone somewhere; point them to something
  • To prove something to be true, correct
  • To reveal or allow something to be seen

arbitrary

Copy vocabulary

US / ˈɑ:bitrəri /

UK / ˈɑrbɪˌtrɛri /

B1
  • adjecitve
  • (Of decisions) unsupported; without any evidence

way

Copy vocabulary

US / weɪ /

UK / we /

A1
  • adverb
  • Used to emphasize the amount of something
  • noun
  • Particular aspect of something being thought about
  • One of various choices that could be made
  • Particular existing condition or state
  • (Often long) distance or length of time
  • How something is done
  • Route to go to a place
  • Small street
  • Usual behavior, emotions or habits of someone

decay

Copy vocabulary

US / dɪˈkeɪ /

UK / dɪˈke /

B1
  • noun
  • Slow loss of physical or mental health
  • verb
  • To be slowly destroyed by natural processes; rot
  • To lose health or strength

length

Copy vocabulary

US / leŋθ /

UK / leŋθ /

A2
  • noun
  • Distance from one end of a pool to the other
  • Measurement of distance or of time

pretty

Copy vocabulary

US / 'prɪtɪ /

UK / ˈprɪti /

A1
  • adjecitve
  • Being attractive to the eye in a simple way
  • adverb
  • Very; to a great degree

apparent

Copy vocabulary

US / ə'pærənt /

UK / əˈpærənt, əˈpɛr- /

A2
  • adjecitve
  • Easy to see or clearly understand
  • Seeming to exist or be true, but may not be

prove

Copy vocabulary

US / pru:v /

UK / pruv /

A2
  • verb
  • To demonstrate truth by providing evidence

worry

Copy vocabulary

US / ˈwʌri /

UK / ˈwɜ:ri /

A1
  • noun
  • Something that causes trouble or concern
  • verb
  • To cause concern or trouble over something

between

Copy vocabulary

US / bɪˈtwi:n /

UK / bɪˈtwin /

A1
  • preposition
  • From one person, thing, or place, to another
  • In the space that separates two objects
  • Among two or more people who share something

error

Copy vocabulary

US / ˈerə(r) /

UK / ˈɛrɚ /

A2
  • noun
  • Something that is not correct; a mistake

they

Copy vocabulary

US / ðeɪ /

UK / ðe /

A1
  • pronoun
  • Two or more people, animals, or things

tidbit

Copy vocabulary

US / ˈtɪdbɪt /

UK / ˈtɪdˌbɪt /

C2
  • noun
  • Small tasty bit of food

very

Copy vocabulary

US / 'verɪ /

UK / ˈvɛri /

A1
  • adjecitve
  • Concerning a large degree or amount
  • adverb
  • A lot; much; many
  • Used to stress or emphasize a noun

believe

Copy vocabulary

US / bɪ'li:v /

UK / bɪˈliv /

A1
  • verb
  • To think or accept that something is true
  • To have a particular opinion about something

bit

Copy vocabulary

US / bɪt /

UK / bɪt /

A1
  • noun
  • Device put in a horse's mouth to control it
  • Small piece of something
  • verb
  • (E.g. of fish) to take bait and be caught

look

Copy vocabulary

US / lʊk /

UK / lʊk /

A1
  • noun
  • Person's beauty or physical attractiveness
  • Particular style of dress, clothes, or appearance
  • The way someone, something appears to be
  • Act of searching for or examining something
  • verb
  • To appear to be; seem
  • Introduction to Video Content
  • The video titled 'Euler line | Special properties and parts of triangles | Geometry | Khan Academy' discusses the special properties and parts of triangles. The video begins by drawing an arbitrary triangle, which is assumed not to be an equilateral triangle. The first property discussed is that of the perpendicular bisectors. The midpoint of each side is identified, and a perpendicular bisector is drawn, creating a line segment that bisects the side at a right angle. Three perpendicular bisectors are drawn for the three sides of the triangle, and it is explained that these lines will intersect at a unique point called the circumcenter. The circumcenter is identified as the point of intersection of the perpendicular bisectors. The video then moves on to discuss the medians of the triangle. It is explained that medians go from each vertex of the triangle to the midpoint of the opposite side. Four medians are drawn for the given triangle, and it is stated that all of these medians intersect at a point called the centroid. The centroid is identified as the point of intersection of the medians. Overall, the video provides an introduction to the special properties and parts of triangles, specifically focusing on the circumcenter and centroid.
  • Subtitles section
  • So I've drawn an arbitrary triangle over here that we will assume is not an equilateral triangle.
  • And let's draw some of the interesting properties of this triangle.
  • So, let's first start with the perpendicular bisectors.
  • So let's say this is the midpoint of this side right over here.
  • So-- draw a little bit closer to the midpoint-- looks like right about there.
  • So this length is equal to this length right over here.
  • And so let me draw a perpendicular bisector.
  • So perpendicular bisector would look something like that for that side.
  • Now let me do it on this side.
  • So just trying to eyeball it, this looks roughly like the midpoint.
  • So this length is going to be equal to this length, and then once again, let me draw a perpendicular bisector, so it's going to go at a 90 degree angle.
  • I can draw a straighter line than that.
  • So that looks pretty good.
  • And it is perpendicular.
  • And then you can imagine I will do it with this side, with side AB.
  • That looks like the midpoint.
  • This length is going to be equal to that length right over there.
  • And then if we draw a perpendicular-- my best attempt to draw this-- it looks something like that.
  • And we've already learned that these three lines will definitely intersect in a unique point right over there, which we call the circumcenter.
  • So let me write it.
  • So this right over there is our circumcenter.
  • This is nothing new.
  • Now let's draw the medians.
  • So, the medians go from each of the vertices to the midpoint of the opposite side.
  • So let me draw.
  • So this is a median, this is a median, this is a median, and then this is-- and all the errors in my drawing will start to become apparent, now that I'm trying to do multiple things with it.
  • But we know all of the medians intersect at the centroid.
  • So this right over here is the centroid.
  • Now let's draw the altitudes of this triangle.
  • So let's draw the altitude.
  • So I'm going to drop a perpendicular right over here.
  • This is one altitude.
  • I will draw another altitude.
  • So remember, it's going to go down like this.
  • Draw another altitude that looks something like that.
  • And then I can draw another altitude from this side, and we know it's going to intersect at this unique point right over here.
  • So I'll try to draw it as neatly as I can.
  • And this is going to be perpendicular, although the way I've drawn it, it doesn't necessarily look that way.
  • And we know that this thing right over here is called an orthocenter.
  • Now the whole reason why I'm doing this, and this is frankly kind of a mind-boggling idea.
  • It's neat enough that each of these points even exists, that three altitudes will intersect in one point, that the three medians intersect in one point, and they have all these neat properties, and that the three perpendicular bisectors intersect in one point.
  • That by itself is neat enough.
  • But what's really neat-- and it's maybe not completely apparent by the way I drew it, because I just drew it free hand-- is that these three points will definitely be on the same line.
  • If this was an equilateral triangle, they would actually be the same point.
  • But for any other triangle there'll be different points, and they will be on the same line.
  • Which is just kind of crazy, because obviously two points define a line, but three points being on the same line is kind of a-- it seems like a very unlikely thing, if you were to just guess it.
  • And I'm going to try to draw it as best as I can.
  • If you were to draw this with a straight edge ruler, it would come out a lot cleaner.
  • But all three points sit on this unique line that, it seems something special or magical about it.
  • And because it's something special or magical, there's one famous mathematician who tends to get all of the most special and mathematical things named after him, because he's the guy who's really explored these things.
  • And we call this the Euler line.
  • And I say that Leonhard Euler-- that looks like ENTER.
  • I say that he gets all of the cool and magical mystical things named after him, because he's also responsible for Euler's identity, which is e to the i pi is equal to negative 1.
  • And we proved this in the calculus playlist, and if none of this makes any sense to you, don't worry.
  • We're only in geometry right now.
  • But he gets to have all the-- This is a magical thing because e comes out of compound interest, and growth and decay, exponential growth and decay.
  • i squared is negative 1-- seems a very bizarre imaginary number.
  • Pi is a ratio of the circumference of a circle to its diameter.
  • And negative 1 is, well, negative 1.
  • And so Euler showed that there's a lot of reason to believe that these four numbers that come from all of these different weird realities of the world are connected in this very tight way.
  • And he also showed that these special points are all on the same line, which tells us something kind of crazy and mystical about our reality.
  • And if that is not enough for you, if you were to take the midpoint on the Euler line between the orthocenter-- I'm not going to prove it here, I'm just going to give you a little bit of a tidbit of it.
  • If you take the midpoint between the orthocenter and the circumcenter-- so let's take this.
  • So I'm going to try to look at it roughly.
  • So it looks like it's right about there.
  • So this length is going to be equal to this length right over here.
  • This point that sits on the Euler line is going to be the center of something called the nine-point circle, which intersects this triangle at nine points.
  • And we'll see this kind of nine interesting points.
  • So let me label that as well.
  • So it's cool enough that these three special points are on the Euler line, but there's actually four special points.
  • And actually, there's a few more than that are kind of interesting.
  • So that orange point right over there is the center of the nine-point circle.
  • And maybe I'll do another video, another video just on that.
  • So anyway, hopefully you found that kind of interesting.