MathDB

2

Part of 1987 Poland - Second Round

Problems(1)

congruent faces in tetrahedron criterion

Source: Polish MO Recond Round 1987 p2

9/9/2024
Prove that the sum of the plane angles at each of the vertices of a given tetrahedron is 180āˆ˜ 180^{\circ} if and only if all its faces are congruent.
geometry3D geometrycongruent trianglestetrahedron