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Find the equation of a line that passes through the points (-4,-3) and (4,-1)

User Paul Wang
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1 Answer

15 votes
15 votes

Answer:

y=x/4 - 2

Explanation:

First, find the slope:

m=(y2-y1)/(x2-x1) ==> slope formula where m=slope

(x1, y1), (x2, y2) ==> (x1=-4, y1=-3) and (x2=4, y2=-1)

Now plug in known values back into the slope formula:

m=(-1-(-3))/(4-(-4))

m=(-1+3)/(4+4)

m=2/8 ==> simplify

m=1/4

y=mx+b ==> slope-intercept equaiton form

-1=(1/4)(4)+b ==> plug in the slope, m=1/4, and a known coordinate: (4,-1)

-1=1+b ==> simplify

-1-1=1-1+b ==> solve for b

b=-2

y=(1/4)x+(-2) ==> plug in b=-2 and m=1/4 back into y=mx+b

y=x/4 - 2

User Tara McGrew
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3.0k points