Question

Given the points (0,1) and (-2,5) and on a line, find its equation in the form y= mx+b.

Answer 1

the desired equation is y = -2x + 1

Explanation:

As we go from (-2, 5) to (0, 1), x increases by 2 and y decreases by 4. Thus, the slope of this line is m = rise / run = -4 / 2, or m = -2.

Starting with y = mx + b, insert the knowns:

1 = -2(0) + b. Then b = 1, and the desired equation is y = -2x + 1.