Identify the slope of the line shown in the graph below: Graph of a vertical line with an x intercept of 4

For this case we have the following line:
 x = 4
 The first thing you should know is that the slope of the line is given by:
 m = (y2-y1) / (x2-x1)
 In this case:
 x2 = x1
 Thus,
 The slope is:
 m = (y2-y1) / (0)
 m = infinity
 Answer:
 The slope of the line is:
 m = infinity