Nets of Polyhedra
A net is a two-dimensional pattern that can be folded to create a three-dimensional shape called a polyhedron.
Think of it this way:
Imagine carefully cutting along the edges of a cardboard box and unfolding it flat on a table. That flat pattern is the net of the box!
What is a Polyhedron?
A polyhedron is a 3D shape with:
- Faces - flat surfaces (polygons)
- Edges - line segments where faces meet
- Vertices - corner points where edges meet
Euler's Formula:
V - E + F = 2
Vertices - Edges + Faces = 2
V - E + F = 2
Vertices - Edges + Faces = 2
Common Polyhedra
| Shape | Faces | Edges | Vertices |
|---|---|---|---|
| Cube | 6 squares | 12 | 8 |
| Tetrahedron | 4 triangles | 6 | 4 |
| Square Pyramid | 1 square + 4 triangles | 8 | 5 |
| Triangular Prism | 2 triangles + 3 rectangles | 9 | 6 |
Interactive 3D Cube and Its Net
Explore this interactive 3D cube. Notice how it has 6 square faces!
Interactive visualization — available in the full lesson