SOLUTION: How do I find the equation of the line which passes throughthe points (2,-1) and (-1,-4)

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Question 212928: How do I find the equation of the line which passes throughthe points
(2,-1) and (-1,-4)
Found 2 solutions by rfer, MathTherapy:
Answer by rfer(16322) About Me  (Show Source):
You can put this solution on YOUR website!
Plot the points
y=mx+b
y=4/3x+(-3)
y=4/3x-3
remember thr rise over the run

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!
(2,-1) and (-1,-4)

We 1st determine the slope, using the slope formula, m = %28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29 -----> %28-4--1%29%2F%28-1-2%29 = %28-3%29%2F-3 = 1

Using the slope, or m = 1, we then plug the information into the point-slope formula to determine our equation

Point-slope formula: y+-+y%5B1%5D+=+m%28x+-+x%5B1%5D%29 ----> y - -1 = 1(x - 2) ----> y + 1 = x - 2 ------> y = x - 3.

Therefore,the equation of the line which passes through the points (2,-1) and (-1,-4) is: highlight_green%28y+=+x+-+3%29