How can i find the rate of change in the graph of the photo?

The rate of change in a linear graph is the slope m of the line. The slope equation is given by
[tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex]where the x's and y's coming from two points in the given graph. For instance, we can choose from the given line:
[tex]\begin{gathered} (x_1,y_1)=(-2,0) \\ (x_2,y_2)=(0,4) \end{gathered}[/tex]By substituying these values into the slope formula, we obtain
[tex]m=\frac{4-0}{0-(-2)}[/tex]which gives
[tex]\begin{gathered} m=\frac{4}{2} \\ m=2 \end{gathered}[/tex]hence, the rate of change is 2.