Answer:
-2
Explanation:
The interval [-6. -4] refers to x values.
At x = -6, in the line in the middle of -4 and -8, y = 0 at the x axis
At x = -4, y = -4. We know this because when the function crosses x = -4, y = -4 at that point.
The average rate of change is equal to (change in y)/ (change in x) = (yfinal - yinitial) / (xfinal - xinitial) (or the other way around in terms of final and initial)
= (-4 - 0) / (-4 - (-6)) = -4 / (-4 + 6) = -4/2 = -2