Question

The graph shows the quadratic function f(x) .

What is the average rate of change for the quadratic function from x = 4 to x = 8?

Answer 1

the average rate of change formula is A(x)= f(x) - f(a)
x - a

Answer 2

-2

Explanation:

The average rate of change would be change in y divided by change in x

Value of the function at x = 4 is 12

Value of the function at x = 8 is 4

Hence,

• change in y is
  `4-12=-8`
• change in x is
  `8-4=4`

Average rate of change from x = 4 to x = 8 is
`(-8)/(4)=-2`