Tetrahedron

Tetrahedron Facts
Notice these interesting things:
	It has 4 Faces
	Each face has 3 edges, and is actually an Equilateral Triangle
	It has 6 Edges
	It has 4 Vertices (corner points)
	and at each vertex 3 edges meet

And for reference:
	Surface Area = √3 × (Edge Length)²
	Volume = (√2)/12 × (Edge Length)³

The tetrahedron also has a beautiful and unique property ... all the four vertices are the same distance from each other! (thanks Ganesh)

And it is the only Platonic Solid with no parallel faces.

Instructions: In "spin" mode it freely spins and will respond to your mouse. In "drag" mode it stops spinning and you can use your mouse to move it. If you cannot see the animation at all, you will need to install "Flash Player".

Note: If you have more than one tetrahedron they are called tetrahedra

(When we say "tetrahedron" we often mean "regular tetrahedron" (in other words all faces are the same size and shape), but it doesn't have to be regular.)

4-Sided Dice? Yes! A tetrahedron that has 4 equal faces has an equal chance of landing on any face.

In fact, you can make fair dice out of all of the Platonic Solids.