We can draw the following lines representing the rise and run of the given graph:
By taking any points you want, for instance with (0, 7) and (4, -3) we got the graph you can see in the above figure. The slope of a line "m" is given by the following formula:

Where the rise is calculated by taking the difference between the y-coordinates of two points and the run by taking the difference in the x-coordinates, then we get:
rise = 7 - (-3) = 7 + 3 = 10
run = 4 - 0 = 4
Then, the slope of the line is
m = 10/4 = 5/2
slope = 5/2