Answer:
6
Check if you have written the function equation properly. If you have, this is the answer
Explanation:
Average rate of change is the first differential of the function
Given function is f(x) = 6x + 5
Rate of change = f'(x) = d/dx(6x) + d/dx(5)
= 6 + 0
= 6
The average rate of change(slope) is a constant throughout all values of the function and so also between[4, 7]