Answer:
NO Slope
Explanation:
slope of the line passing through the points (5, 4) and (5, -5)
slope = y2 - y1  = -5 - 4  =  -9 
 x2 - x1 5 - 5 0
see attached.
in this graph of a line x = 5, no matter what the value of y is.
the horizontal change is 0 and the vertical change is any y value
therefore, there is NO Slope