There are five Platonic (regular) solids: tetrahedron, 4 triangular sides hexahedron (i.e. cube), 6 square sides octahedron, 8 triangular sides dodecahedron, 12 pentagonal sides icosahedron, 20 triangular sides Each face of a Platonic solid must be a regular polygon and each face must be congruent. Also, the solid must be convex and the number of
