To find the slope, you divide the difference of the y-coordinates of a point on a line by the difference of the x-coordinates. It is expressed as:
slope = (y2 - y1) / (x2-x1)
slope = 8-(-7) / 4 - 4
slope = 15 / 0
slope = undefined <------ SECOND OPTION
The line should be vertical where the slope is undefined. Hope this answers the question. Have a nice day.
