What are platonic solids?

Answer 1

The Platonic solids, also called the regular solids or regular polyhedra, are convex polyhedra with equivalent faces composed of congruent convex regular polygons.

In geometry, a Platonic solid is a convex regular polyhedron. These are the three-dimensional analogs of the regular polygons. There are precisely five such figures (shown below). The name of each figure derives from the number of faces in each — which are 4, 6, 8, 12, and 20 respectively. They are unique in that the sides, edges and angles are all congruent.

There are only five geometric solids that can be made using a regular polygon and having the same number of these polygons meet at each corner. The five Platonic solids (or regular polyhedra) are the tetrahedron, cube, octahedron, dodecahedron, and icosahedron.

Answer 2

You will find your answer here:

http://mathworld.wolfram.com/PlatonicSolid.html

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