How do you write an equation given (-3,4), (1,-4)?

1 Answer
Anjali G
Nov 7, 2016

Point-slope form: y-4=-2(x+3)y−4=−2(x+3)
Slope-intercept form: y=-2x-2y=−2x−2

Explanation:

Assuming you mean a line that passes through these two points, use point-slope form:
y-y1=m(x-x1)y−y1=m(x−x1)

To find the slope, m, use the slope formula m = (y2-y1)/(x2-x1)m=y2−y1x2−x1
(-3,4) and (1,-4):
m=(-4-4)/(1+3)m=−4−41+3
m=-8/4=-2m=−84=−2

Now, plug in the slope and either point into point-slope form:
y-4=-2(x+3)y−4=−2(x+3)

To convert this to slope intercept form, isolate y and simplify:
y-4=-2x-6y−4=−2x−6
y=-2x-2y=−2x−2

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