projections of 3 perpendiculars on 4th face concurrent, in tetrahedron
Source: Sharygin 2005 X-XI CR 22
August 20, 2019
geometry3D geometrytetrahedronCentroidconcurrencyconcurrent
Problem Statement
Perpendiculars at their centers of gravity (points of intersection of medians) are restored to the faces of the tetrahedron. Prove that the projections of the three perpendiculars to the fourth face intersect at one point.