A solid surrounded by four or more planes is called "polyhedron"Especially, all sides are composed of congruent regular polygons"Regular polyhedron"Is a solid with the most beautiful symmetry, it is ...

This media is in the public domain (free of copyright restrictions). You can copy, modify, and distribute this work without contacting the Smithsonian. For more information, visit the Smithsonian's ...

https://doi.org/10.4169/amer.math.monthly.124.3.265 https://www.jstor.org/stable/10.4169/amer.math.monthly.124.3.265 The five Platonic polyhedra combine identical ...

For most people, the word “polyhedron” conjures up an image of a cube, a tetrahedron, or something similar—a solid figure with flat faces. If the polyhedron is regular, each face has the same size and ...

The highlight of the 13th and final book of Euclid's Elements was the proof that there are just five "Platonic solids". Recall that a regular polygon is a plane figure with all sides and angles equal, ...

A 3D shape with all straight edges and flat faces is a polyhedron. Other 3D shapes with least one curved surface are not polyhedra. A 3D shape with regular polygonal faces, meeting at equal angles, is ...

This media is in the public domain (free of copyright restrictions). You can copy, modify, and distribute this work without contacting the Smithsonian. For more information, visit the Smithsonian's ...