Question

An art studio charges a start-up fee to cover art supplies, plus an additional fee per class. The graph shows the total cost for different numbers of classes. Find and interpret the rate of change and initial value

Answer 1

Answer/Step-by-step explanation:

✔️The rate of change can be calculated using the coordinates of any two points on the graph. Let's use (2, 60) and (3, 75):

$rate of change = \frac{y_2 - y_1}{x_2 - x_1} = \frac{75 - 60}{1} = \frac{15}{1} = 15$

Rate of change (m) = 15

✅In the context of this situation, the rate of change can be interpreted to be the additional fee per class. Thus, an additional fee per class cost $15.

✔️Initial value is the same as the y-intercept.

To find the y-intercept (b), substitute m = 15, x = 2, and y = 60 into y = mx + b.

Thus:

60 = 15(2) + b

60 = 30 + b

60 - 30 = b

30 = b

b = 30

The initial value/y-intercept = $30

✅In this context, $30 is the start-up fee to cover art supplies.