Polyhedron with eight faces.
A regular octahedron is a regular convex polyhedron in which all of its faces are isometric equilateral triangles. It is one of the five Platonic solids. It has 6 vertices, 12 edges, and 8 faces.
Formulas
Based on the length \(a\) of the edge, we can calculate the area A and volume V of a regular octahedron:
\(A=2\sqrt{3}{a^2}\)
\(V=\dfrac{\sqrt{2}}{3}{a^3}\)