Question

The Area of a circle is 3.14 square miles. What is the circles circumference

Answer 1

`2\pi`

Explanation:

The area of a circle is
`\pi`
`r^(2)`, where r is the radius.

Let r be the radius of this circle.

We can write that:

`\pi`
`r^(2)` =
`\pi` (according to the problem)

Divide by
`\pi` on both sides:

`r^(2)` = 1

Take the square root (the negative value, r = -
`√(1)`, is not viable as you cannot have a negative length as the radius):

r =
`√(1)` = 1

The circumference of a circle is
`2\pi r` (r being the radius), so we plug in r=1:

circumference =
`2\pi r` =
`2\pi`*1 =
`2\pi`.