TOT 2000 Spring OS1 sum of areas PAB, PCD = sum of areas PAD,PCB
Source:
May 11, 2020
areasareageometrymidpoint
Problem Statement
The diagonals of a convex quadrilateral meet at . The sum of the areas of triangles and is equal to the sum of areas of triangles and . Prove that is the midpoint of either or . (Folklore)