12.) What is a tetrahedron? Now construct a tetrahedron.

A regular tetrahedron, referred to as "the" tetrahedron, is a Platonic solid, regular solids and polyhedra that are convex with equivalent faces made of congruent convex regular polygons, that contains four polyhedron vertices, six polyhedron edges, and four equilateral triangular faces. Tetrahedra are considered uniform polyhedra, polyhedra with identical polyhedron vertices, a Wenninger model, and is described by the Schläfli symbol {3,3} and the Wythoff symbol 3|23. This has seven axes of symmetry. This is also the ONLY convex polyhedron that has four faces.

 

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