Substitution method 2 | Systems of equations | 8th grade | Khan Academy
A1 A2 B1 B2 C1 C2
number
US / ˈnʌmbə(r) /
•UK / ˈnʌmbɚ /
- 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
tell
US / tel /
•UK / tɛl /
- 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
solve
US / sɒlv /
•UK / sɑ:lv /
- verb
- To figure out a way to handle a difficult problem
constraint
US / kənˈstreɪnt /
•UK / kənˈstrent /
- noun
- Thing preventing you moving or acting; restriction
different
US / ˈdɪfrənt /
•UK / ˈdɪfrənt /
- adjecitve
- Not of the same kind; unlike other things
like
US / laɪk /
•UK / laɪk /
- 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
US / ðæt /
•UK / ðæt, ðət /
- 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’
steep
US / sti:p /
•UK / stip /
- adjecitve
- Very expensive
- Rising or falling very sharply, as a cliff or hill
- Involving a quick increase or decrease
- verb
- To fill with a certain quality, e.g. history
- To put a thing in a liquid for some time
what
US / wɒt /
•UK / hwɑt, hwʌt, wɔt, wʌt,hwət, wət /
- 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
everywhere
US / ˈevriweə(r) /
•UK / ˈevriwer /
- adverb
- Every place
right
US / raɪt /
•UK / raɪt /
- 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
mean
US / mi:n /
•UK / min /
- 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
down
US / daʊn /
•UK / daʊn /
- 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
must
US / məst /
•UK / mʌst /
- noun
- Something that is necessary or required
- other
- (Used to state that something ought to be true)
- Used to say something is required or necessary
then
US / ðen /
•UK / ðɛn /
- 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
whenever
US / wenˈevə(r) /
•UK / hwɛnˈɛvɚ /
- adverb
- At any or every time that
first
US / fɜ:st /
•UK / fɚst /
- 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
US / ɡet /
•UK / ɡɛt /
- 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
second
US / 'sekənd /
•UK / ˈsɛkənd /
- adjecitve
- 2nd; the one following first
- noun
- Unit of time; one sixtieth of a minute
- Short period of time that you wait for someone
- (Do) soon
- verb
- To agree to support a proposal at a meeting
crazy
US / 'kreɪzɪ /
•UK / ˈkrezi /
- 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
want
US / wɔnt /
•UK / wɑnt, wɔnt /
- noun
- Something you desire or wish for
- State or condition of poverty
- verb
- To desire or wish for something; hope for a thing
same
US / seɪm /
•UK / sem /
- adjecitve
- Being equal in quality and amount
- Identical; not different
- Not changing; constant
wacky
US / 'wækɪ /
•UK / ˈwæki /
- adjecitve
- Quite strange, but in a creative way
but
US / bət /
•UK / bʌt,bət /
- conjunction
- Used before you say something different, opposite
give
US / ɡɪv /
•UK / ɡɪv /
- 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
really
US / ˈri:əli /
•UK / ˈriəˌli, ˈrili /
- adverb
- Used to stress something that is said; definitely
- In a true or accurate manner
- Very
distribute
US / dɪˈstrɪbju:t /
•UK / dɪˈstrɪbjut /
- verb
- To hand out or give to people
- To send products to stores to sell
- To spread something over an area
not
US / nɒt /
•UK / nɑt /
- adverb
- Word indicating the negative
- (Used to form the negative of verbs)
our
US / 'aʊə(r) /
•UK / aʊr /
- determiner
- Belonging to us
equal
US / 'i:kwəl /
•UK / ˈikwəl /
- adjecitve
- Same in shape, size, or number
- verb
- To add up or be the same as
now
US / naʊ /
•UK / naʊ /
- 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
substitute
US / 'sʌbstɪtju:t /
•UK / ˈsʌbstɪˌtut, -ˌtjut /
- noun
- A person or thing acting in place of another
- verb
- To perform the tasks instead of someone else
- To replace one person or thing for another
can
US / kæn /
•UK / kən,kæn /
- 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
equation
US / ɪˈkweɪʒn /
•UK / ɪˈkweʒən, -ʃən /
- noun
- Mathematical statement showing things to be equal
- Complex set of different facts, ideas or issues
graph
US / græf /
•UK / ɡræf /
- noun
- Image expressing numerical data in lines or shapes
- verb
- To show data using images
for
US / fə(r) /
•UK / fɔr,fə /
- preposition
- Used to show the purpose, or need of something
time
US / taɪm /
•UK / taɪm /
- 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
why
US / waɪ /
•UK / hwaɪ, waɪ /
- adverb
- Question word to ask for a reason
- exclamation
- (Used to express surprise or approval)
just
US / dʒʌst /
•UK / dʒʌst /
- 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
US / laɪn /
•UK / laɪn /
- 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
those
US / ðəʊz /
•UK / ðoz /
- determiner
- The people or things we are talking about
- pronoun
- The objects far from the speaker
set
US / set /
•UK / sɛt /
- adjecitve
- Prepared for something; ready
- noun
- Complete group of something
- Place where a television show or movie is filmed
- Group of games in a tennis match
- Device that receives radio or television signals
- verb
- To make a clock state or ring at a particular time
- To decide upon or choose something
- To make something ready for use (e.g. table)
- To decide on a price for something
- To become hard (of glue, concrete etc.)
- To be located in a specific place or time
- To put (e.g. a vase) down carefully in a place
- To put someone in a certain condition or state
- (Of the sun) to go lower than the horizon
well
US / wel /
•UK / wɛl /
- 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
explicitly
US / ɪk'splɪsɪtlɪ /
•UK / ɪk'splɪsɪtlɪ /
- adverb
- Clearly; specifically
system
US / 'sɪstəm /
•UK / ˈsɪstəm /
- adjecitve
- Working in an organized, logical way
- noun
- Set of organized, planned ideas that work together
slope
US / sləʊp /
•UK / sloʊp /
- noun
- Angle of a decline, e.g. where a road dips down
- Surface on which people can ski
- verb
- To have one end that is not as high as the other
solution
US / səˈlu:ʃn /
•UK / səˈluʃən /
- noun
- Mix of a liquid and a solid or a gas
- Way to solve or deal with a problem
forward
US / 'fɔ:wəd /
•UK / ˈfɔrwəd /
- adjecitve
- Toward what is ahead; in front
- Acting in a socially aggressive manner; pushy
- adverb
- Toward the front in place; in front
- Toward a future time; to a more advanced state
- verb
- To send something to another address or person
other
US / 'ʌðə(r) /
•UK / ˈʌðər /
- adjecitve
- A thing different from that mentioned
- determiner
- (Something) else; not the first (one)
- pronoun
- Being the one and only thing of that category
one
US / wʌn /
•UK / wʌn /
- 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
make
US / meɪk /
•UK / mek /
- 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
repetitive
US / rɪˈpetətɪv /
•UK / rɪˈpɛtɪtɪv /
- adjecitve
- Doing or saying the same things many times
multiple
US / ˈmʌltɪpl /
•UK / ˈmʌltəpəl /
- adjecitve
- Having or involving more than one of something
- noun
- Number produced by multiplying a smaller number
- Shop with many branches
term
US / tɜ:m /
•UK / tɚm /
- noun
- Conditions applying to an agreement, contract
- Length of time something is expected to happen
- Fixed period of weeks for learning at school
- The (precise) name given to something
- verb
- To call; give a name to
this
US / ðɪs /
•UK / ðɪs /
- 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
you
US / jʊ /
•UK / ju /
- pronoun
- Person someone is speaking or writing to
- Person or people in general
let
US / let /
•UK / lɛt /
- verb
- To allow someone to do something
- Introducing a suggestion to do something together
- To rent a house, etc. to others
the
US / ðə /
•UK / ðə /
- 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
clearly
US / ˈklɪəlɪ /
•UK / ˈklɪrlɪ /
- adverb
- In a way that is easy to understand; obviously
pretty
US / 'prɪtɪ /
•UK / ˈprɪti /
- adjecitve
- Being attractive to the eye in a simple way
- adverb
- Very; to a great degree
subtract
US / səbˈtrækt /
•UK / səbˈtrækt /
- other
- To take away a value or amount from another
- verb
- To take away a value or amount from another
they
US / ðeɪ /
•UK / ðe /
- pronoun
- Two or more people, animals, or things
very
US / 'verɪ /
•UK / ˈvɛri /
- adjecitve
- Concerning a large degree or amount
- adverb
- A lot; much; many
- Used to stress or emphasize a noun
both
US / bəuθ /
•UK / boθ /
- determiner
- Used to refer to two things at the same time
- pronoun
- Used to refer to two things at the same time
result
US / rɪ'zʌlt /
•UK / rɪˈzʌlt /
- noun
- Something produced through tests or experiments
- Final score of a competition, election or game
- verb
- To be the outcome of other causes and effects
bit
US / bɪt /
•UK / bɪt /
- 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
cancel
US / 'kænsl /
•UK / ˈkænsəl /
- verb
- To end a legal, business, or other agreement
- To stop a planned event from happening
look
US / lʊk /
•UK / lʊk /
- 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
multiply
US / ˈmʌltɪplaɪ /
•UK / ˈmʌltəˌplaɪ /
- verb
- To increase in number by reproducing/having babies
- To increase something by a large quantity
- To have increased by a large quantity
- To calculate two numbers e.g. 2 x 4
rewrite
US / ˌri:'raɪt /
•UK / riˈraɪt /
- verb
- To write again to improve, or correct errors
move
US / mu:v /
•UK / muv /
- 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
all
US / ɔ:l /
•UK / ɔl /
- adverb
- Completely; totally
- determiner
- Being every one of something
- pronoun
- 100% of something; the complete amount
already
US / ɔ:lˈredi /
•UK / ɔlˈrɛdi /
- adverb
- Having happened or been done before this time
telltale
US / ˈtelteɪl /
•UK / ˈtɛlˌtel /
- noun
- Someone who discloses information intentionally
shift
US / ʃɪft /
•UK / ʃɪft /
- 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
inconsistent
US / ˌɪnkənˈsɪstənt /
•UK / ˌɪnkənˈsɪstənt /
- adjecitve
- Not tying together logically or with the facts
divide
US / dɪ'vaɪd /
•UK / dɪˈvaɪd /
- verb
- To split numbers by another number, e.g. 6 / 2 = 3
- To separate something into equal pieces
satisfy
US / ˈsætɪsfaɪ /
•UK / ˈsætɪsˌfaɪ /
- verb
- To make someone happy because they got their wish
- To do what is required in order to finish
actually
US / ˈæktʃuəli /
•UK / ˈæktʃuəli /
- adverb
- Used to add new (often different) information
use
US / ju:s /
•UK / ju:s /
- 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
write
US / raɪt /
•UK / raɪt /
- 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
here
US / hɪə(r) /
•UK / hɪr /
- adverb
- In this place; at this location, position or time
intersect
US / ˌɪntə'sekt /
•UK / ˌɪntɚˈsɛkt /
- verb
- To divide something by crossing it
plus
US / plʌs /
•UK / plʌs /
- noun
- A benefit or advantage
- preposition
- In addition; add
- In addition to; Indicates a number above
- Having a value greater than zero
side
US / saɪd /
•UK / saɪd /
- 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
negative
US / 'neɡətɪv /
•UK / ˈnɛɡətɪv /
- 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
onto
US / ˈɒntə /
•UK / ˈɑnˌtu, -tə, ˈɔn- /
- preposition
- Towards a certain direction/into a certain area
see
US / si: /
•UK / si /
- 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)
clear
US / klɪə(r) /
•UK / klɪr /
- 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
algebraically
US / ˌældʒɪˈbreɪkli /
•UK / ˌældʒəˈbreɪɪkli /
- adverb
- In an algebraic manner
could
US / kəd /
•UK / kʊd /
- other
- Past form of 'can' to mean have ability
- Used to ask for something politely, or to offer
know
US / nəʊ /
•UK / noʊ /
- 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
have
US / həv /
•UK / hæv /
- 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
parallel
US / 'pærəlel /
•UK / ˈpærəˌlɛl /
- 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
with
US / wɪð /
•UK / wɪð, wɪθ /
- 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
call
US / kɔ:l /
•UK / kɔl /
- 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
leave
US / li:v /
•UK / liv /
- noun
- Permission to do something
- Vacation time; time off work
- verb
- To go away from; depart
- To gift property to someone after you die
- To allow something to continue happening
- To let something remain unused or available
- To let something or someone remain somewhere
from
US / frəm /
•UK / frʌm, frɑm,frəm /
- preposition
- Starting at a particular place, time or level
form
US / fɔ:m /
•UK / fɔrm /
- noun
- Sports team or person's current winning record
- Document you complete when making an application
- Visible shape or style; type; kind
- verb
- To organize something such as a club or group
- To develop; to come into a shape or substance
- To make something into a particular shape
internalize
US / ɪnˈtɜ:nəlaɪz /
•UK / ɪnˈtɜ:rnəlaɪz /
- verb
- To accept attitudes, behavior as part of yourself
out
US / aʊt /
•UK / aʊt /
- 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
US / 'əʊvə(r) /
•UK / ˈovɚ /
- 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
minus
US / ˈmaɪnəs /
•UK / ˈmaɪnəs /
- 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
two
US / tu: /
•UK / tu /
- number
- 2
something
US / ˈsʌmθɪŋ /
•UK / ˈsʌmθɪŋ /
- 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
and
US / ənd /
•UK / ənd, ən,ænd /
- conjunction
- Used to refer to two or more things
- Plus; in addition; on top of that
- Used to introduce an action that follows another
guy
US / ɡaɪ /
•UK / ɡaɪ /
- noun
- Man; boy; any person