Answer:
The average rate of change is -3.
Step-by-step explanation:
We are given the function:

And we want to find the average rate of change from <em>x </em>= 0 to <em>x </em>= 3.
In other words, we will compute the function at the two endpoints, and then find the slope of the line that crosses the two points.
For our first endpoint at <em>x</em> = 0, our function evaluates to:

So, our first point is (0, 9).
For our second endpoint at <em>x</em> = 3, our function evaluates to :

So, our second point is (3, 0).
Then by the slope formula, our average rate of change will be:
