Question

Identify the slope of the line shown in the graph below:

Graph of a vertical line with an x intercept of 3

Answer 1

I believe the slope of any vertical line is "undefined" because slope= rise(change in y values)/ run(change in x values).

Therefore, the slope for a horizontal line is
m= 0/(x2-x1).

However, for a vertical line the x-values are the values that are not changing. So, m= (y2-y1)/0. It is not possible to divide anything by zero. So, the slope of a vertical line is reported as m= undefined.

Any questions?