The Platonic solids are regular 3-D figures. Regular means that all the edges are of equal length, all the angles of equal measure, and all faces are congruent shapes. The solids were discovered by the Pythagoreans but later described by the Greek philosopher Plato. | ||||

Tetrahedron |
Hexahedron |
Octahedron |
Dodecahedron |
Icosahedron |

Made of 4 equilateral triangles It has the smallest volume for its surface |
Made of 6 squares Commonly called a cube |
Made of 8 equilateral triangles It rotates freely when held by two opposite vertices |
Made of 12 equilateral pentagons |
Made of 20 equilateral triangles It has the largest volume for its surface area |

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