MMO 367 Moscow MO 1957 intersection of 2 squares in 8 points
Source:
March 20, 2021
areafixedsqauresgeometry
Problem Statement
Two rectangles on a plane intersect at eight points. Consider every other intersection point, they are connected with line segments, these segments form a quadrilateral. Prove that the area of this quadrilateral does not vary under translations of one of the rectangles.