Question

Which is the best estimate of the average rate of change of f(x) over the interval
−
60
≤
x
≤
−
20
?

A.
–4

B.
–2

C.
2

D.
4

Answer 1

I don’t have the graph or the values of f at x = −60 and x = −20. To find the average rate of change you need

average rate = [f(−20) − f(−60)] / [−20 − (−60)] = [f(−20) − f(−60)] / 40.

So read f(−60) and f(−20) from the graph (or give them here) and compute that difference divided by 40. Then match the result to the choices:

- If (f(−20) − f(−60)) = −160 → slope = −4 (A)
- If = −80 → slope = −2 (B)
- If = 80 → slope = 2 (C)
- If = 160 → slope = 4 (D)

Upload the graph or tell me f(−60) and f(−20) and I’ll compute the correct choice.