Respuesta :

A = πr^2
r^2 = A/π

r = √(A/π)

Hope this helps!

Answer:

The required formula is [tex]r=\sqrt{\frac{A}{\pi}}[/tex].

Step-by-step explanation:

The given formula is

[tex]A=\pi r^2[/tex]

We have to rearrange the given formula for r.

Divide both sides by π.

[tex]\frac{A}{\pi}=\frac{\pi r^2}{\pi}[/tex]

[tex]\frac{A}{\pi}=r^2[/tex]

Square root both the sides.

[tex]\sqrt{\frac{A}{\pi}}=\sqrt{r^2}[/tex]

[tex]\sqrt{\frac{A}{\pi}}=r[/tex]

Therefore the required formula is [tex]r=\sqrt{\frac{A}{\pi}}[/tex].