Question

S=2πr2+2πrh; Solve for h.

Answer 1

 S = 2πRh + 2πR2 

S -2πR2= 2πRh 

(S -2πR2) / (2πR) = h

Answer 2

$S=2\pi r^2+2\pi rh$

We need to solve for h. It means we need to get 'h' alone

First we subtract $2\pi r^2$ on both sides

$S - 2\pi r^2=2\pi r^2- 2\pi r^2+2\pi rh$

$S - 2\pi r^2=2\pi rh$

Now we divide by  $2\pi r$ on both sides

$\frac{S - 2\pi r^2}{2\pi r} = \frac{2\pi rh}{2\pi r}$

$\frac{S - 2\pi r^2}{2\pi r} =h$

We got h alone. Solved for h

$h=\frac{S - 2\pi r^2}{2\pi r}$