V = [tex] \frac{1}{2} [/tex]πr²h Multiply both sides by 2 2V = πr²h Divide both sides πh [tex] \frac{2V}{\pi h} [/tex] = r² Find the square root of both sides [tex] \sqrt{ \frac{2V}{\pi h} } [/tex] = r Switch the sides to make it easier to read r = [tex] \sqrt{ \frac{2V}{\pi h} } [/tex]