Question

The points (6,r) and (9, 9) lie on a line with slope 5. Find the missing coordinate r.

Answer 1

r = -6

Explanation:

Use the slope formula and solve for r.

slope = y2 -y1

x2 -x1

Since you know all the numbers except for r, plug everything in and you get:

5 = 9 - r

9 - 6

So then do the arithmetic, you find that 9 - r = 15. So r must = -6.