MathDB
Cute Combo Geo

Source: Sharygin 2022 P13

March 4, 2022
geometry

Problem Statement

Eight points in a general position are given in the plane. The areas of all 5656 triangles with vertices at these points are written in a row. Prove that it is possible to insert the symbols "++" and "āˆ’-" between them in such a way that the obtained sum is equal to zero.