This is not a function, therefore, the slope is undefined.
I would propose using a VERTICAL LINE TEST. This test is to check vertically if there are more than one coordinates/points in one vertical line. That line is vertical, and there are many points, which makes it not a function. And if it is not a function, then the slope is undefined.
The slope, also, is the average rate of change. The formula you use to find the slope is [tex] \frac{y(2) - y(1)}{x(2) - x(1)} [/tex]. You would take any coordinates and insert them into this formula.
