Question

A circle has a radius of 7 inches. What is the area of the circle?

A. 21.98 in^2
B. 43.96 in^2
C. 153.86 in^2
D. 615.44 in^2

Please include ALL work! <3

Answer 1

C. 153.86 in^2

Explanation:

The area of a circle can be found using the following formula.

`a=\pi r^2`

where r is the radius.

We know the radius is 7 inches. Therefore, we can substitute 7 in for r.

`r= 7 in`

`a=\pi (7 in)^2`

Evaluate the exponent.

(7 in)^2= 7 in * 7 in= 49 in^2

`a= \pi * 49 in^2`

Let's use 3.14 for pi.

`a= 3.14 * 49 in^2`

Multiply 3.14 and 49

3.14 * 49=153.86

`a= 153.86 in^2`

The area of the circle is 153.86 square inches. Therefore, C is the correct answer.

Answer 2

C. 153.86 in^2

`area = \pi {r}^(2) \\ r = 7 \\ a = (22)/(7) * {7}^(2)`

`a = (22)/(7) * 49 \\ a = 22 * 7 = 154 {cm}^(2)`

Explanation:

`area = \pi {r}^(2) \\ a \: = 3.14 * {7}^(2) \\ a \: = 3.14 * 49 = 153.86 {cm}^(2)`