Surface area of a prism

What is the surface area of a prism?

Easy!

It is the area of each shape that makes up the prism.

For the square prism we looked at, this is the area of the two squares at each end and the four rectangles.

Let’s say that the squares have sides of 2cm and the length of the rectangles are 10cm. What is the surface area of the prism?

This prism is made up of four rectangles that are 2cm x 10cm and two squares that are 2cm x 2cm.

The area of each square is $2cm \times 2cm = 4cm^2$

The area of each rectangle is $2cm \times 10cm = 20cm^2$

The surface area of the prism is therefore $2 \times 4cm^2 + 4 \times 20cm^2 = 8cm^2 + 80cm^2 = 88cm^2$