Answer
slope is undefined
Work Step by Step
RECALL:
slope = $\dfrac{y_2-y_1}{x_2-x_1}$ where $(x_1, y_1)$ and $(x_2, y_2)$ are the coordinates of the two points on the line.
Use the points on the line $(2, 0)$ and $(2, 1)$ to obtain:
slope = $\dfrac{1-0}{2-2}=\dfrac{1}{0}\space \text{undefined}$
