Question

S=2*3.14r^2 2*3.14rh for h

Answer 1

$\sf\\S=2\pi r^2+2\pi rh\\\\Subtract\ 2\pi r^2\ on\ both\ sides.\\\\S-2\pi r^2=2\pi rh\\\\Divide\ by\ 2\pi r\ on\ both\ sides.\\\\h= \frac{S}{2\pi r}-\frac{2\pi r^2}{2\pi r}\\\\\\{\boxed{h=\frac{S}{2\pi r}-r}$

Answer 2

If you would like to solve S = 2 * 3.14 * r^2 + 2 * 3.14 * r * h for h, you can do this using the following steps:

S = 2 * 3.14 * r^2 + 2 * 3.14 * r * h
S - 2 * 3.14 * r^2 = 2 * 3.14 * r * h       /2
S/2 - 3.14 * r^2 = 3.14 * r * h              /3.14
S/6.28 - r^2 = r * h                           /r
h = S/(6.28*r) - r

The correct result would be h = S/(6.28*r) - r.