So we need to find the slope of the line that contains (17,-12) and (17,8). Given two points (a,b) and (c,d) the slope of the line that contain them is given by the difference of y-values divided by the difference of x-values:
[tex]m=\frac{d-b}{c-a}[/tex]Using this the slope we need to find is:
[tex]m=\frac{8-(-12)}{17-17}=\frac{20}{0}[/tex]We have a division by 0 which means that the answer is that the slope is undefined.
