Answer
$ \frac{-a}{b-e}$
Work Step by Step
We use the equation for slope:
$m = \frac{y_2-y_1}{x_2-x_1}$
$m_{AC} = \frac{2b-2e}{2a-0}=\frac{b-e}{a}$
The altitude is perpendicular to this, so the slope of the altitude is the opposite reciprocal of this value, which is:
$m= \frac{-a}{b-e}$
