How it works
A net is a solid unfolded flat. Add the areas of its faces to get the surface area.
A box has 6 faces in 3 matching pairs.
A square pyramid has a square base and 4 triangle faces.
Worked examples
A box
- A box is 6 ft by 5 ft by 4 ft.
- Faces: 30, 24 and 20, each twice. 30 + 24 + 20 = 74.
- Double: 74 × 2 = 148 square feet.
Count equal faces
- In a triangular prism, count which faces are 6 by 7.
- Look for matching faces on the net.
- Matching faces have the same area.
A pyramid
- A square pyramid has a 4 m by 4 m base and 4 triangle faces.
- Base: 4 × 4 = 16. Each triangle of base 4 and height 4: 4 × 4 ÷ 2 = 8, and 4 of them make 32.
- 16 + 32 = 48 square meters.
A taste of the worksheet
These are the first problems of set A. The printable sheet has many more, with an answer key.
- A net is a solid unfolded flat. A net with 6 equal squares folds into which solid?
- A net has one square and four triangles. Which solid does it fold into?
- How many squares are in a net of this cube? Answer: ___