Question 1092432
This one is fun, and easy in the end!

{{{S=2*pi*r^2 + 2*pi*r^2*h}}}

subtract {{{2*pi*r^2}}} from both sides to give

{{{S-2*pi*r^2 = 2*pi*r^2*h}}}

then isolate h by dividing both sides by {{{2*pi*r^2}}}

this will give {{{(S-2*pi*r^2)/(2*pi*r^2) = h}}}

which simplifies to:

{{{h = S/2*pi*r^2 - 1}}}


yay!