Answer
The slope is undefined.
Work Step by Step
We are given the two points $(5, 9)$ and $(5, -6)$.
Let's use the formula to find the slope $m$ given two points:
$m = \frac{y_2 - y_1}{x_2 - x_1}$,
where $(x_1, y_1)$ and $(x_2, y_2)$ are points on the line.
Let's plug in the values into this formula:
$m = \frac{-6 - 9}{5 - 5}$
Subtract the numerator and denominator to simplify:
$m = \frac{-9}{0}$
The slope is undefined.
