Question

Find the value of r so that the line through (2,8) and (r,-4) has a slope of -3

Answer 1

6

Explanation:

The slope (m) is given by ...

m = (y2 -y1)/(x2 -x1)

Filling in the given values, we have an equation we can solve for r.

-3 = (-4 -8)/(r -2)

r -2 = -12/-3 . . . . . multiply by (r-2)/-3

r = 6 . . . . . . . . . . . add 2