we know that
Average Rate of Change. is the change in the y-value divided by the change in the x-value for two distinct points on the graph
So

in this problem

substitute the values in the formula above

Divide by
both numerator and denominator

therefore
the answer is

Suppose we let
, so that
.
Also, recall the double angle identity for cosine:

So, we can rewrite and compute the integral using the substitution, as





Y=-1.5x + 8
hope this helps :) (please mark brainliest!)