If you look at the point (-2,0) you can see that it sits directly on the line above 2. If you also at the point (3,4) you can see that its also sitting directly in the middle, where the line runs through it. Using this information we can use Rise/Run.
Rise/Run = Y/X
from (-2, 0) you rise 4 and you run 5 to the right to land on (3,4).
This is one of many ways you can calculate The slope from a graph!
