Prove that there exists a straightline g -IMO ShortList 1973
Source:
September 22, 2010
combinatoricspartitionpoint setgeometrycombinatorial geometryIMO Shortlist
Problem Statement
Let be positive integers. Consider in a plane two disjoint sets of points and consisting of and points, respectively, and such that no three points of the union are collinear. Prove that there exists a straightline with the following property: Each of the two half-planes determined by on ( not being included in either) contains exactly half of the points of and exactly half of the points of