Prove that if two altitudes of a tetrahedron intersect, then so do the other two altitudes.
Problem
Source: Israel Grosman Memorial Mathematical Olympiad 1997 p4
Tags: altitudes, tetrahedron, 3D geometry, geometry
Source: Israel Grosman Memorial Mathematical Olympiad 1997 p4
Tags: altitudes, tetrahedron, 3D geometry, geometry
Prove that if two altitudes of a tetrahedron intersect, then so do the other two altitudes.