Consider the graph:
Let's graph the rise and the run
The red line is the run and the green line is the rise, see that run = 3 units and rise = 9 units, the slope will be
[tex]\text{slope=}\frac{\text{rise}}{\text{run}}[/tex]
Therefore the slope will be
[tex]\text{slope}=\frac{9}{3}=3[/tex]
Then the slope is 3.
