Which expression below gives the average rate of change of the function g(x) = -x2 - 4x on the interval 6 ≤ x ≤ 8 ?

Question

asked Jul 23, 2019 68.7k views

2 Answers

Zulukas · Answer 1 · 2019-07-27T11:17:57+0000

Answer: -18

Step-by-step explanation:

Average rate of change is slope:
(y_(2)-y_(1))/(x_(2)-x_(1)) . Need to find the y-coordinates:

g(x) = -x² - 4x

g(6) = -(6)² - 4(6)

= -36 - 24

= -60

⇒ (6, -60)

g(8) = -(8)² - 4(8)

= -64 - 32

= -96

⇒ (8, -96)

m =
(-96 - (-60))/(8 - 6)

=
(-36)/(2)

= -18