Step-by-step explanation:
If r and h are the radius and height of the cylinder, then its surface area A is given by :
[tex]A=2\pi r^2+2\pi rh[/tex] ....(1)
We need to find the cylinder's height in terms of its radius and surface area. Subtracting [tex]2\pi rh[/tex] on both sides, we get :
[tex]A-2\pi r^2=2\pi rh+2\pi r^2-2\pi r^2\\\\A-2\pi r^2=2\pi rh[/tex]
Dividing both sides by [tex]2\pi r[/tex]. So,
[tex]\dfrac{A-2\pi r^2}{2\pi r}=\dfrac{2\pi rh}{2\pi r}\\\\h=\dfrac{A-2\pi r^2}{2\pi r}[/tex]
Hence, this is the required solution.