Question

How do you find the average rate of change through an interval

Answer 1

In order to find average rate of change over an interval, do the y2-y1/x2-x1. Solve y for x=9 and x= 4
y2 = -3(9-4)^2 + 3 = -72
y1 = -3(4-4)^2 + 3 = 3

Now, x2 matches with y2 and and x1 matches with y1 obviously...
-72 - 3/9 - 4 = -15