Question

he formula for the surface area of a sphere is A = 4πr2. Which equation correctly solves the equation for r?

Answer 1

A = 4 pi r^2
r^2 = A / 4 pi
r = sqrt A / 2 sqrt pi

Answer 2

The solution for the required variable is
`r=\sqrt{(A)/(4\pi)}`

Explanation:

Consider the provided formula.

`A=4\pi r^2`

We need to solve the formula for r.

Divide both sides by 4π.

`(A)/(4\pi)=(4\pi r^2)/(4\pi)`

`r^2=(A)/(4\pi)`

`r=\sqrt{(A)/(4\pi)}`

We will not take the negative value as r can not be a negative number.

Hence, the solution for the required variable is
`r=\sqrt{(A)/(4\pi)}`