The surface area of a 3 dimensional shape is the area that we would have to paint if we wanted to paint the shape. To find the surface area of any shape we simply find the area of each of its faces and add those areas together.

With a cylinder there are three faces. As well as the circles on either end their is a rectangle that is wrapped around (try bending a piece of paper into a tube to convince yourself that the “curved” face on a cylinder is actually a rectangle.

Examples

Exercise

Let’s complete exercise 17D on page 288 of the textbook:

The answers are below: