## Algebra 1: Common Core (15th Edition)

Rate of Change: $2$ For every extra hour of study, the grade increases by $2$.
The formula for Constant rate of change is $\frac{△y}{△x}$. Let's take 2 sets of coordinates and plug it in to this formula. $\frac{87 - 85}{6 - 5} = \frac{2}{1} = 2$ The constant rate of change is $2$. As you can see, for every extra hour studied, the grade increases by $2$, which is what the constant rate of change mean.