Question

What's the slope of the line (80,90)

Answer 1

m = 90/80 = 9/8

Explanation:

If you meant the line through the origin (0, 0) and (80, 90), then the change in x is 80 and that in y is 90. The slope is m = (change in y) / (change in x), or

m = 90/80 = 9/8

Answer 2

Eighth of an inch per foot