Answer:
-5/8
Step-by-step explanation:
Step 1: Find the slope of line d. As we move from point (5, 2) to point (10, 10), x increases by 5 and y increases by 8. Thus, the slope of line d is
m = rise / run = 8/5.
Step 2: Find the negative reciprocal of this m = 8/5. Doing so will give us the slope of line e or of any other line perpendicular to line d:
Slope of line e: -(5/8) = -5/8