Question

The circumference of a circle is 7π m. What is the area, in square meters? Express your answer in terms of π

Answer 1

A ≈ 3.9

Explanation:

How to solve

• Using the formulas

A=πr2

C=2πr

• Solving for A

A=C2

4π=72

4·π ≈ 3.8993

Therefore, the circle in square meters in the nearest tenths is A ≈ 3.9

Answer 2

`12.25\pi\,\,m^2`

Explanation:

Given: Circumference of a circle =
`7\pi\,\,m`

To find: Area of a circle in terms of
`\pi`

Solution:

Let r denotes radius of a circle.

Circumference of a circle =
`2\pi r`

`7\pi=2\pi r\\7=2r`

Divide both side by
`\pi`

`3.5\,m=r`

Area of a circle =
`\pi r^2`

Put
`r=3.5\,\,m`

`=\pi (3.5)^2\\=12.25\pi\,\,m^2`