[tex]h = V / ( \pi r^2)[/tex]
Okay, so we already have the volume equation for a cylinder here.
[tex]V = \pi r^2 h[/tex]
Since we need to find the height(h), we need to basically isolate it in the equation. To do that we just have to divide both sides by (pi * r^2), where we end up with:
[tex]V / (\pi r^2) = h(\pi r^2) / (\pi r^2)[/tex]
then
[tex]V / ( \pi r^2) = h[/tex]
[tex]h = V / ( \pi r^2)[/tex]