SOLUTION: How do you figure out the equation of a line modeled by the table like: x y 0 -5 1 -1 2 3 3 7

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Question 117506: How do you figure out the equation of a line modeled by the table like:
x y
0 -5
1 -1
2 3
3 7
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
Use the two-point form of a line.
First, choose two of the specified points. Let's pick the first two (0,-5) and (1,-1).

Then get the two-point form:

y-y%5B1%5D=%28%28y%5B1%5D-y%5B2%5D%29%2F%28x%5B1%5D-x%5B2%5D%29%29%28x-x%5B1%5D%29,

And plug in the numbers from the coordinate values in the points chosen.

y-%28-5%29=%28%28-5-%28-1%29%29%2F%280-1%29%29%28x-0%29

Do the arithmetic:

y%2B5=%28-4%2F-1%29x
y%2B5=4x

Then, just to be neat, put your equation into either standard form ax%2Bby=c or slope-intercept form y=mx%2Bb
4x-y=5
y=4x-5

Use one of the other points in your table to check your work.
3=4%2A2-5, yep!