> In geometry, how many faces does a tetrahedron have?And the answer: four. The prefix "tetra" means four. In geometry, a tetrahedron is a 3D shape that hasfour faces, like a pyramid.Photo credit: public domain.While a tetrahedron might seem simple enough, it hasmany unique qualities much like that of the other platonic solids[https://www.askqotd.com/platonic-solids/]. Each face of a tetrahedron offers anequilateral triangle, and beautifully, all four vertices are the same distancefrom each other. Tetrahedrons are also the only platonic solid with no parallelfaces.You might also recognize this shape from games like Dungeons & Dragons — itsperfectly even sides and angles make for fair dice. This designation is onlygranted to shapes which have an equal chance of landing on any face, and thetetrahedron's four equal faces make that pretty darn easy. The tetrahedron is actually the only polyhedron that has four faces. It is alsothe only simple polyhedron that has no polyhedron diagonals (as in, no facediagonals or space diagonals). Interestingly, a regular tetrahedron can beformed using six of the face diagonals of a cube. The vertices of thetetrahedron coincide with four of the cube's vertices, making it fit snugly withvery little effort. See for yourself:Photo credit: technologyuk.netLearn more about the uses and importance of thetetrahedron below.