labelling vertices of a tetrahedron
Source: Simon Marais 2017 B1
April 29, 2021
geometrycombinatorics3D geometrytetrahedron
Problem Statement
Maryam labels each vertex of a tetrahedron with the sum of the lengths of the three edges meeting at that vertex.
She then observes that the labels at the four vertices of the tetrahedron are all equal. For each vertex of the tetrahedron, prove that the lengths of the three edges meeting at that vertex are the three side lengths of a triangle.