Question

7. This graph represents how much Sarah charges to babysit one child. Cost Idollarg) 1 17 Time hours What is the rate of change of the cost with respect to the time?

Answer 1

To calculate the rate of change, you have to use the following formula

$k=\frac{y}{x}$

Choose a point

(1, 8), (2, 16) or (5, 32)

And calculate k

$\begin{gathered} k=\frac{16}{2} \\ k=8 \end{gathered}$

The rate of change of the cost with respect the time is k=8 $/hour