Finding the average rate of change of a function HELP: 5 stars to best answer

Find the average rate of change of the function from x^1 to x^2.

f(x) = -3x^2 - x from x^1 = 5 to x^2 = 6

CHOICES:
1/2

-1/6

-2

-34

FIVE STARS TO FIRST BEST ANSWER

Average rate of change of

-3x^2 - x from x=5 to x=6

( f (6) - f (5) ) / (6 - 5)

f (6) = - 114
f (5) = - 80

(- 114 - (-80)) / 1 = - 34 <===

Hello,

The value of f(x) when x=5 is -3(5)² -5 = -80
The value of f(x) when x=6 is -3(6)² -5 = -114

F(x) decreased by -34 while x increased by +1 ( from 5 to 6)

The average change is (change of y)/(change of x) = -34/1 = -34

Choice 4 !

Hope it helped

Bue