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Sum of the exterior angles of convex polygon | Geometry | Khan Academy

Video vocabulary

hexagon

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US / ˈheksəgən /

UK / ˈheksəgɑ:n /

C1
  • noun
  • Flat, six-sided shape

minus

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US / ˈmaɪnəs /

UK / ˈmaɪnəs /

A2
  • adjecitve
  • Being close to the bottom of a letter grade
  • noun
  • Negative quality; disadvantage
  • Sign that indicates subtraction
  • preposition
  • Being less than zero in number
  • Used when subtracting one number from another
  • verb
  • To take one number away from another; subtract

out

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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

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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

and

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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

finally

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US / ˈfaɪnəli /

UK / ˈfaɪnəli /

A1
  • adverb
  • used especially at the beginning of a sentence to introduce the last point or idea
  • After a long time or some difficulty

keep

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US / ki:p /

UK / kip /

A1
  • noun
  • Large, strong tower in the middle of a castle
  • Money spent on you so you can live in a place
  • verb
  • To continue doing something; not to stop
  • To stop balls going in a goal in sports
  • To not give back or return something
  • (Of food) to not spoil or not rot
  • To take possession of something to own, e.g. a pet
  • To have and continue to hold something
  • To do something that you have promised or agreed
  • To stay in a certain place or condition
  • To maintain the rules

something

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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

any

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US / 'enɪ /

UK / ˈɛni /

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

particular

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US / pəˈtɪkjələ(r) /

UK / pɚˈtɪkjəlɚ, pəˈtɪk- /

B2
  • adjecitve
  • One specific (one)
  • Having firm ideas about what is desirable
  • Being special or more than is typical

think

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US / θɪŋk /

UK / θɪŋk /

A1
  • verb
  • To have an idea about something without certainty
  • To have an idea, opinion or belief about something

call

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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

correspond

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US / ˌkɒrəˈspɒnd /

UK / ˌkɔ:rəˈspɑ:nd /

B1
  • verb
  • To have similarity or equality with something
  • To write letters or emails to someone

manipulate

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US / mə'nɪpjʊleɪt /

UK / məˈnɪpjəˌlet /

B1
  • verb
  • To try to control others to gain an advantage
  • To handle or work in a skillful manner

pentagon

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US / 'pentəɡən /

UK / ˈpɛntəˌɡɑn /

C1
  • noun
  • A five-sided shape

two

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US / tu: /

UK / tu /

A1
  • number
  • 2

feeling

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US / ˈfi:lɪŋ /

UK / ˈfilɪŋ /

A1
  • noun
  • Sensation or emotion you experience
  • verb
  • To be aware of or experience an emotion, sensation
  • To sense through direct contact; touch

same

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US / seɪm /

UK / sem /

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

angle

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US / ˈæŋgl /

UK / ˈæŋɡəl /

B1
  • noun
  • Place where two lines or surfaces meet

now

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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

measure

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US / ˈmeʒə(r) /

UK / ˈmɛʒɚ /

A1
  • noun
  • Plan to achieve a desired result
  • Tool used to calculate the size of something
  • verb
  • To determine the value or importance of something
  • To calculate size, weight or temperature of

exterior

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US / ɪkˈstɪəriə(r) /

UK / ɪkˈstɪriɚ /

B1
  • adjecitve
  • External; of the outside part
  • noun
  • Outside layer or surface
  • Way a person appears or seems to other people

involve

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US / ɪn'vɒlv /

UK / ɪnˈvɑlv /

A2
  • verb
  • To have or be included as a part of something

pick

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US / pɪk /

UK / pɪk /

A1
  • noun
  • Sharp tool used for breaking the ground
  • Item selected from a group of choices
  • verb
  • To take fruit or vegetables from a plant or tree
  • To decide on a thing from various choices; select
  • To remove (flower, etc.) with your fingers

supplementary

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US / ˌsʌplɪˈmentri /

UK / ˌsʌplɪˈmentri /

B1
  • adjecitve
  • Functioning in a supporting capacity

would

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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

sum

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US / sʌm /

UK / sʌm /

A2
  • noun
  • Amount when all is added together; total
  • verb
  • To add two or more numbers together; total

want

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US / wɔnt /

UK / wɑnt, wɔnt /

A1
  • noun
  • Something you desire or wish for
  • State or condition of poverty
  • verb
  • To desire or wish for something; hope for a thing

video

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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

color

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US / 'kʌlə(r) /

UK / ˈkʌlɚ /

A1
  • noun
  • Quality of things you can see, e.g. red, blue
  • Pink or red in your face, e.g. after being ill
  • The shade of someone's skin e.g. black, or yellow
  • verb
  • To change or affect someone's opinion
  • To make something colorful using colored pencils

maybe

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US / ˈmeɪbi /

UK / ˈmebi /

A1
  • adverb
  • Possibly but not certainly; perhaps

not

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US / nɒt /

UK / nɑt /

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

can

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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

apply

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US / ə'plaɪ /

UK / əˈplaɪ /

A1
  • verb
  • To spread a substance or liquid over a surface
  • To commit your time and effort to doing something
  • To make something useful in a certain situation
  • To be relevant for a situation
  • To ask formally for (job, permission etc.)

but

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US / bət /

UK / bʌt,bət /

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

convex

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US / ˈkɒnveks /

UK / ˈkɑ:nveks /

C1
  • adjecitve
  • Having a surface that curves outward like a ball

inward

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US / ˈɪnwəd /

UK / ˈɪnwərd /

B1
  • adverb
  • At the inside of

ago

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US / əˈgəʊ /

UK / əˈgoʊ /

A1
  • adverb
  • At a specified length of time in the past

figure

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US / ˈfiɡə /

UK / ˈfɪɡjɚ /

A1
  • noun
  • Your body shape
  • Numbers in a calculation
  • Doll-like thing meant to represent a person
  • Picture or diagram giving information in a text
  • Person who is very important or famous
  • Shape of a person seen indistinctly or in outline
  • Amount that is expressed in numbers
  • verb
  • To appear in a game, play or event
  • To calculate how much something will cost
  • To understand after thinking; work out

move

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US / mu:v /

UK / muv /

A1
  • noun
  • Act of moving a playing piece in chess, etc.
  • An action; doing something
  • Step taken to achieve a goal
  • verb
  • To cause someone to have certain emotions
  • To cause something to change to a different place
  • To change where people live or a business operates
  • To take action to do or achieve something

transversal

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US / træns'vɜ:səl /

UK / træns'vɜ:səl /

A1
  • adjective
  • (of a line) intersecting a system of lines.
  • noun
  • A transversal line.

way

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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

they

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US / ðeɪ /

UK / ðe /

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

believe

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US / bɪ'li:v /

UK / bɪˈliv /

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

bit

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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

counterclockwise

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US / ˌkaʊntəˈklɒkwaɪz /

UK / ˌkaʊntərˈklɑ:kwaɪz /

A1
  • other
  • In a direction opposite to the direction in which the hands of a clock move
  • In the direction opposite to the rotation of the hands of a clock

look

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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

regular

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US / ˈregjələ(r) /

UK / ˈrɛɡjəlɚ /

A2
  • adjecitve
  • Having an equal amount of space or time in between
  • Occurring or being done frequently
  • Being normal, usual, or average
  • noun
  • Customers who frequently visit a place
  • Soldier who has a permanent job in the army

apologize

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US / ə'pɒlədʒaɪz /

UK / əˈpɑləˌdʒaɪz /

A2
  • verb
  • To say sorry because of a mistake or injury

all

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US / ɔ:l /

UK / ɔl /

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

its

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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”

pretty

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US / 'prɪtɪ /

UK / ˈprɪti /

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

several

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US / ˈsevrəl /

UK / ˈsɛvərəl,ˈsɛvrəl /

A1
  • adjecitve
  • Many of
  • pronoun
  • More than two but not a large amount

confused

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US / kənˈfju:zd /

UK / kənˈfjuzd /

A2
  • adjecitve
  • Being hard to understand
  • verb
  • To make something unclear or hard to understand

work

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US / wɜ:k /

UK / wɚk /

A1
  • adjecitve
  • Activity completed in order to make money
  • noun
  • The product of some artistic or literary endeavor
  • Everything created by an author, artist, musician
  • Activity you do in order to make money
  • Place of employment
  • Final product or result of a some labor or effort
  • verb
  • To bring into a specific state of success
  • To be functioning properly, e.g. a car
  • To do your job in your company or workplace
  • To make an effort to do something
  • To operate a machine or device

simple

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US / 'sɪmpl /

UK / ˈsɪmpəl /

A1
  • adjecitve
  • Not hard to understand or do; not complex
  • Having only a few parts; not complex
  • Being ordinary or normal
  • Being plain; without a lot added for style

show

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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

add

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US / æd /

UK / æd /

A1
  • verb
  • To include as well
  • To put two things or numbers together, e.g. 2+2

take

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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

clockwise

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US / ˈklɒkwaɪz /

UK / ˈklɑkˌwaɪz /

B1
  • adjecitve
  • In the same direction as a clock's hands

for

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US / fə(r) /

UK / fɔr,fə /

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

redraw

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US / ˌri:ˈdrɔ: /

UK / ˌriːˈdrɔː /

B2
  • verb
  • To redo an image using pen or pencil and paper

time

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US / taɪm /

UK / taɪm /

A1
  • noun
  • Speed at which music is played; tempo
  • Point as shown on a clock, e.g. 3 p.m
  • Number of hours, minutes needed to do something
  • Occasion when something happens
  • Period or occasion that something occurred
  • Period in history or the past
  • Something measured in minutes, hours, days, etc.
  • How long an event takes; duration
  • verb
  • To check speed at which music is performed
  • To choose a specific moment to do something
  • To measure how long an event takes, e.g. a race
  • To schedule something to occur at a specific moment

imply

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US / ɪmˈplaɪ /

UK / ɪmˈplaɪ /

A2
  • verb
  • To suggest something, without saying it directly

sorry

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US / ˈsɒri /

UK / ˈsɑ:ri /

A1
  • exclamation
  • What you say to admit you were wrong
  • adjecitve
  • Causing others to feel pity; poor
  • Feeling regret or sympathy about wrong thing

green

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US / gri:n /

UK / ɡrin /

A1
  • adjecitve
  • Color of young leaves
  • Covered with vegetation, e.g. grass
  • Concerned about protecting the environment
  • The color of young leaves
  • Lacking in experience/knowledge due to being young
  • Being not fully grown or ripe, as in fruit
  • noun
  • Large grassy area
  • used as a part of a name of a place (UK)

dent

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US / dent /

UK / dɛnt /

B2
  • noun
  • Place on a car, etc. where it has been pushed in
  • verb
  • To make a depression on a (metal) surface

well

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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

just

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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

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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

talk

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US / tɔ:k /

UK / tɔk /

A1
  • noun
  • Style of speaking
  • Discussion between two countries
  • Giving information in front of people; lecture
  • Saying things or ideas to someone with words
  • verb
  • To make a formal speech about something
  • To say things or ideas to someone with words

also

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US / 'ɔ:lsəʊ /

UK / ˈɔlso /

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

kind

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US / kaɪnd /

UK / kaɪnd /

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

you

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US / jʊ /

UK / ju /

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

able

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US / 'eɪbl /

UK / ˈebəl /

A2
  • adjecitve
  • Skilled; good at something
  • Having the ability to do something

congruent

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US / ˈkɒŋgruənt /

UK / ˈkɑ:ŋgruənt /

C1
  • adjecitve
  • Having the same shape and size

let

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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

might

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US / maɪt /

UK / maɪt /

A1
  • other
  • Used to politely request an action
  • Used to express that something could happen
  • Power, strength, force or influence

the

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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

cave

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US / keɪv /

UK / kev /

A2
  • noun
  • Large hole in the side of a cliff or hill
  • verb
  • To give in to pressure

this

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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

into

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US / 'ɪntə /

UK / ˈɪntu /

A1
  • preposition
  • Moving or going inside something
  • In the same direction as; in the direction of
  • So as to become; taking the state of

one

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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

other

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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

process

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US / prə'ses /

UK / ˈprɑsˌɛs, ˈproˌsɛs /

A2
  • noun
  • Dealing with official forms in the way required
  • Set of changes that occur slowly and naturally
  • verb
  • To organize and use data in a computer
  • To deal with official forms in the way required
  • To prepare by treating something in a certain way
  • To adopt a set of actions that produce a result
  • To convert by putting something through a machine

clear

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US / klɪə(r) /

UK / klɪr /

A1
  • adjecitve
  • Empty; without anything in it or on it
  • Being certain and without doubt
  • Being without any streaks, spots, or cracks
  • Easy to understand; well-explained; obvious
  • adverb
  • Completely; entirely; through the whole of
  • Away from; free from
  • verb
  • To recover from or remove a problem
  • To get rid of the entire contents of
  • To give permission for something to happen
  • To make a place or surface empty by removing
  • To prove that someone is not guilty or to blame

draw

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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

see

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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)

have

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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

last

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US / lɑ:st /

UK / læst /

A1
  • adjecitve
  • Most recent; the latest
  • The one before
  • adverb
  • Final; with nothing following; after all others
  • Most recent; the latest
  • determiner
  • The one at the end
  • verb
  • To remain or continue for a certain period of time

parallel

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US / 'pærəlel /

UK / ˈpærəˌlɛl /

B1
  • adjecitve
  • (Of two lines) at equal distance from each other
  • (Of computer operation) happening at the same time
  • Very similar and often occurring at the same time
  • noun
  • A line on a map a set distance from the equator
  • verb
  • To be equal to, or like, something else
  • To compare

algebraically

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US / ˌældʒɪˈbreɪkli /

UK / ˌældʒəˈbreɪɪkli /

C1
  • adverb
  • In an algebraic manner

interior

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US / ɪn'tɪərɪə(r) /

UK / ɪnˈtɪriɚ /

B1
  • adjecitve
  • Being the inside part of a building, car etc.
  • noun
  • Part of country that is far from the border, coast
  • Remote central area of a continent

could

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US / kəd /

UK / kʊd /

A1
  • other
  • Past form of 'can' to mean have ability
  • Used to ask for something politely, or to offer

remember

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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

afraid

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US / əˈfreɪd /

UK / əˈfred /

A1
  • adjecitve
  • Worried that something bad will happen; scared

shift

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US / ʃɪft /

UK / ʃɪft /

A2
  • adjecitve
  • (Of work) starting at a certain time, as at night
  • noun
  • A change in a persons plans, opinions or beliefs
  • Period of work starting at a certain time
  • verb
  • To change in position or direction
  • To move something from one place to another

should

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US / ʃʊd /

UK / ʃʊd /

A1
  • other
  • Used to indicate what is proper or reasonable

actually

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US / ˈæktʃuəli /

UK / ˈæktʃuəli /

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

use

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US / ju:s /

UK / ju:s /

A1
  • noun
  • Ability to employ something
  • Need to enable it to work
  • Permission to do something with something
  • Act of spending money
  • Operation of a machine for its function
  • verb
  • To have; to eat, drink, consume etc.
  • To need to operate or work
  • To operate a machine, e.g. a computer
  • To treat a person badly
  • To do something with, for a task or purpose

side

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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

plus

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US / plʌs /

UK / plʌs /

A2
  • noun
  • A benefit or advantage
  • preposition
  • In addition; add
  • In addition to; Indicates a number above
  • Having a value greater than zero

polygon

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US / ˈpɔli:ˌgɔn /

UK / ˈpɑliˌɡɑn /

A1
  • noun
  • Closed plane figure bounded by straight sides

will

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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

either

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US / ˈaɪðə(r) /

UK / ˈiðɚ, ˈaɪðɚ /

A1
  • adjecitve
  • One of two (used when there is a choice of two)
  • adverb
  • (After negative statements) likewise, in addition
  • conjunction
  • Used as the first of two connected things
  • determiner
  • Used as the first of two connected things
  • pronoun
  • The one or the other

here

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US / hɪə(r) /

UK / hɪr /

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

try

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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

straight

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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

divide

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US / dɪ'vaɪd /

UK / dɪˈvaɪd /

A2
  • verb
  • To split numbers by another number, e.g. 6 / 2 = 3
  • To separate something into equal pieces

obviously

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US / ˈɒbviəsli /

UK / ˈɑːbviəsli /

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

once

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US / wʌns /

UK / wʌns /

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

about

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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)

again

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US / ə'ɡen /

UK / əˈɡɛn /

A1
  • adverb
  • One more time, once more

different

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US / ˈdɪfrənt /

UK / ˈdɪfrənt /

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

like

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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

that

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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’

what

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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

concave

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US / 'kɒn'keɪv /

UK / kɑnˈkev, ˈkɑnˌkev /

C1
  • adjecitve
  • Hollow; curved inward

find

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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

mean

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US / mi:n /

UK / min /

A1
  • adjecitve
  • Being good at
  • Nasty; unkind
  • Not liking to spend money; cheap; stingy
  • noun
  • Average of a set of numbers
  • verb
  • To express a particular idea or thought
  • To intend to do something in particular
  • To have a particular meaning or value

get

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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

number

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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

down

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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

then

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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

right

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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

adjacent

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US / əˈdʒeɪsnt /

UK / əˈdʒesənt /

B1
  • adjecitve
  • Being close or near to a border, wall, or point

each

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US / i:tʃ /

UK / itʃ /

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

triangle

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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
  • Subtitles section
  • Several videos ago, I had a figure that looked something like this.
  • I believe it was a pentagon or a hexagon.
  • And what we had to do is figure out the sum of the particular exterior angles of the hexagon.
  • So it would have been this angle, which we call a, this angle b, c, d, and e.
  • And the way that we did it the last time, we said, well, a is going to be 180 degrees minus the interior angle that is supplementary to a.
  • And then we did that for each of the angles.
  • And then we figured out we were able to algebraically manipulate it.
  • We were able to figure out what the sum of the interior angles were using dividing it up into triangles, and then use that to figure out the exterior angles.
  • And it was a bit of an involved process.
  • What I want to show you in this video is there's actually a pretty simple and elegant way to figure out the sum of these particular exterior angles of this polygon.
  • And it actually works for any convex polygons when you're picking these particular exterior angles, I should say.
  • And so the way to think about it is you can just redraw the angles.
  • So let's just draw each of them.
  • So let me draw this angle right over here.
  • We could call it angle a, or maybe the measure of this angle is a.
  • Either way, let me draw it right over here.
  • So this is going to be a congruent angle right over here.
  • It's going to have a measure of a.
  • Now let me draw angle b.
  • And I'm going to draw it adjacent to angle a.
  • And what you could do is think about it.
  • Maybe if we drew a line right over here that was parallel to this line, then the measure of this angle right over here would also be b, because this obviously is a straight line.
  • It would be like a transversal.
  • These are corresponding angles.
  • So if we wanted to draw an adjacent angle, b adjacent to a, you could do it like that.
  • Or whatever angle this is, its measure is b.
  • And now it's adjacent to a.
  • And now let's draw the same thing for c.
  • We could draw a parallel line to that right over here.
  • And then this angle would also be c.
  • And if we want it to be adjacent to that, we could draw it right over here.
  • So that angle is c.
  • So c would look something like this.
  • Then we can move on to d.
  • Once again, let me do that in a different color.
  • You could do d.
  • D could be right over here.
  • Or you could shift it down over here to look like that.
  • Or you could shift it over here to look like that.
  • If we just kept thinking about if all of these lines were parallel to each other.
  • So let's just draw d like this.
  • So this line, once again, is going to be parallel to that line.
  • And then finally, you have e.
  • Finally, you have angle e.
  • And once again, you could draw a line that is parallel to this right over here.
  • And this right over here would be angle e.
  • Or you could draw it right over here.
  • You would draw it right over here.
  • And when you see it drawn this way, it's clear that when you add up the measure, this angle a, b, c, d, and e, you're going all the way around the circle.
  • Either way, you could be going clockwise or you could be going counterclockwise.
  • But you're going all the way around the circle.
  • And so the sum of these angles are just going to be, so a plus b plus c plus d plus e is just going to be 360 degrees.
  • And this will actually work, as I said, for any convex polygon.
  • When I say convex polygon, I mean one that's not dented inwards, one that's kind of, so just to be clear what I'm talking about, it would work for any polygon that is kind of, I don't want to say regular.
  • Regular means it has the same sides and same angles.
  • But it's not dented.
  • So this is a convex polygon.
  • This right here is a concave polygon.
  • So let me draw it this way.
  • So this right over here would be a concave polygon.
  • I'm going to draw it as having the same number of sides.
  • So I just kind of dented these two sides right over there.
  • And did I do that right?
  • Let me see.
  • Let me do it the same number of sides.
  • So I want to do that, that, that, that, and then that's the same side over there.
  • Let me draw it like that.
  • And then like that.
  • This has 1, 2, 3, 4, 5, 6 sides.
  • This has 1, 2, 3, 4, 5, 6 sides.
  • This is concave.
  • Sorry, this is convex.
  • This is a convex polygon.
  • This is a concave polygon.
  • And the way I remember it is it is kind of caved inwards.
  • And so what we just did would apply to any, if we're trying to find these particular exterior angles of any convex polygon, I afraid, I apologize ahead of time if I've confused them all because I have a feeling that I might have.
  • This applies to any convex polygon.
  • And so once again, if you take this angle and add it to this angle and add it to this angle, add it to this angle, add it to that angle, and add it to that angle, and I'm not implying that they're all going to be the same.
  • I just drew it that way.
  • I could show you that they are different angles.
  • So I could say that one in green and that one in some other color.
  • I think you get the idea.
  • They can all be different.
  • But if you shift the angles like this, you'll see that they just go around the circle.
  • So once again, they'll just add up to 360 degrees.