Determine rate of change of function f(x)= 3x^2-7x^2-18x-8 on given intervals:
(a) -2 ≤x ≤ -1 (b) -1 ≤ x≤ 4 (c) Graph function on the calculator on interval -3 ≤ x ≤ 5 (or wider). Reproduce the copy of graph on paper and use the graph to demonstrate why average rate of change has values you found on interval.