Calculate the average rate of change over the interval [1, 3] for the following function. f(x)=4(5)^x a. -260 b. 260 c. 240 d. -240

Because we cannot see the function, and do not know it's coordinates, we can set the value of x equal to 1, and then 3, and use the coordinate pairs to solve for the rate of change (slope).

4(5)^1

4(5)

20

Our first coordinate pair is 1, 20.

4(5)^3

4(125)

500

Our second coordinate pair is 3, 500.

Now, apply the slope formula:

500 - 20 / 3 - 1

480 / 2

240

c. (3,2,6) is the answer.