What is the coefficient in the expression shown? 42 + 2c

15

Step-by-step explanation:

The function is;

f(x) = x² + 9x

We are to find the average rate of change from point = 1 to point = 5

Average rate of change =  where h is the change in x-axis

When x = 1 , f(x) = 1² + 9(1) = 10

When x = 5, f(x) = 5² + 9(5) = 70

f(x + h) - f(x) = 70 - 10 = 60

h = 5 - 1 = 4

So average rate of change = = 15