Question

I need help with #20

Answer 1

Hey there!

Formula given :

A = πr²

Solve for r

A / π = r²

r = √( A / π )

Hope it helps!

Answer 2

Hope this helps.
i have solved the equation to help you get a better of how to demonstrate this in the future.

Answer 3

A=pi r^2
sqrt(A)=pi r
sqrt(A)/pi=r

Answer:sqrt(A)/pi=r

(sqrt(A) means the square root of A)