Solution:
The vertical change between two points is called the rise.
The vertical change (dy) is the difference between the y-coordinates of the points.
The horizontal change is called the run.
The horizontal change (dx) is the difference between the x-coordinates of the points.
The slope equals the rise divided by the run. The slope is also the average rate of change.
Given:
[tex]\begin{gathered} A(0,0) \\ B(1,3) \end{gathered}[/tex]where;
[tex]\begin{gathered} x_1=0 \\ y_1=0 \\ x_2=1 \\ y_2=3 \end{gathered}[/tex]a) The vertical change (dy) is calculated as shown below;
[tex]\begin{gathered} =y_2-y_1 \\ =3-0 \\ =3 \end{gathered}[/tex]Therefore, the vertical change (rise) is 3.
b) The horizontal change (dx) is calculated as shown below;
[tex]\begin{gathered} =x_2-x_1 \\ =1-0 \\ =1 \end{gathered}[/tex]Therefore, the horizontal change (run) is 1.
c) The average rate of change (slope) is given by;
[tex]\begin{gathered} m=\frac{y_2-y_1}{x_2-x_1}=\frac{rise}{\text{run}} \\ m=\frac{3}{1} \\ m=3 \end{gathered}[/tex]Therefore, the average rate of change (slope) is 3.