Tetrahedron Day - March 4

Today is a day to celebrate the least-sided of the platonic solids, the regular tetrahedron.

A regular tetrahedron is formed by putting 4 identical equilateral triangles together into a convex polyhedron. A non-regular tetrahedron would still consist of 4 triangles, but they would be different sizes and shapes.

The tetrahedron is also a type of pyramid. A pyramid is a polyhedron with a polygon as a base where each vertex connects to another point on a different plane as the base. Many of the pyramids built by people use a square base, and thus are not tetrahedrons. Every tetrahedron is a pyramid, but not every pyramid is a tetrahedron.

We celebrate tetrahedrons on March (3rd month) 4 because it's composed of triangles (3-sided polygons), and 4 of them.

By KoenB - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=5513755


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