Answer:
D sqrt( A ) sqrt(pi) / pi = r
Explanation:
The area of a circle is given by
A = pi r^2
To find r
Divide each side of the equation by pi
A / pi = pi r^2 /pi
A / pi = r^2
Take the square root of each side
sqrt(A / pi )= sqrt( r^2)
sqrt(A / pi )= r
We do not like leaving square roots in the denominator, so multiply by sqrt(pi)/sqrt(pi))
sqrt(A / pi ) *sqrt(pi)/sqrt(pi))
sqrt( A ) sqrt(pi) / pi = r