Mathematics for IGCSE & O level - Equations (Section 8 - No. 41)
The formula for the curved surface area of a cylinder is S = 2πrh. Rearrange this formula to solve for r.
r = S / 2πh
r = S * 2πh
r = 2πh / S
r = S - 2πh
Explication
Divide both sides by 2πh.