Answer
$\frac{2}{3}$
Work Step by Step
The slope measures the ratio of the vertical change to the horizontal change between 2 points on a line.
We can write the slope as m= (vertical change)/(horizontal change)
In this example, the vertical change of the roof is 8 feet and the horizontal change is 12 feet.
Therefore, $m=\frac{8}{12}=\frac{2}{3}$