Hello people happy thanksgiving but i need help

= -4

Step-by-step explanation:

If y = f(x) is a function then the average rate of change for f(x) between the interval a ≤ x ≤ b is given by

.

Now, in this case the function is given by f(x) = - 4x + 40 and the interval is 1 ≤ x ≤ 3.

Therefore, f(1) = - 4(1) + 40 = 36 and f(3) = - 4(3) + 40 = 28

So, the average rate of change is =  (Answer)