If the area (in square units) of the region under the curve of the function f (x) = 5, on the interval from x=a to x=8 is 20 square units, what is the value of a?

Answers: 4, 5, 6, 7, or 8?

8.

Step-by-step explanation:

In the question it says x=a then says x=8 if you do the common process of elimination you can concluded the a=8.

a = 4

Step-by-step explanation:

The function y = f (x) = 5 is simply a horizontal straight line

the interval x=a and x = 8 represent vertical straight lines that intersect x = a and x = 8.

Hence the area above the x-axis that is bound by f (x) on the top and x=a & x=8 on the sides is simply a rectangle with height = 5 and length = (8 - a), and its area is given by

area = height x length = 5 (8-a)

we are given that the area = 20,

hence

area = 20 = 5 (8-a)

(8-a) = 20/5

8-a = 4

-a = 4 - 8

-a = - 4

a = 4