Question

Given the area of a circle is 64(pi) how do you find the radius of the circle?

Answer 1

See the entire solution process below:

Explanation:

The formula for determining the area of a circle is:

`A = pir^2`

Substituting the value from the problem, `64pi` for `A` and solving for `r` gives:

`64pi = pir^2`

We can divide each side of the equation by `color(red)(pi)`

`(64pi)/color(red)(pi) = (pir^2)/color(red)(pi)`

`(64color(red)(cancel(color(black)(pi))))/cancel(color(red)(pi)) = (color(red)(cancel(color(black)(pi)))r^2)/cancel(color(red)(pi))`

`64 = r^2`

We can now take the square root of each side of the equation to find the radius `r`:

`sqrt(64) = sqrt(r^2)`

`8 = r`

`r = 8`

The radius of the circle is `8`.