Question

The function y=f(x)is graphed below. What is the average rate of change of the function f(x) on the interval 7≤x≤8?

Answer 1

40

Explanation:

the average rate of change of f(x) in the closed interval [ a, b ] is

`(f(b)-f(a))/(b-a)`

here [ a, b ] = [ 7, 8 ] , then

f(b) = f(8) = 20 ← point (8, 20 ) on graph

f(a) = f(7) = - 20 ← point (7, - 20 ) on graph

average rate of change =
`(20-(-20))/(8-7)` =
`(20+20)/(1)` = 40