MathDB
equilateral of side 1 is covered by 5 congruent equilateral of side s<1

Source: Switzerland - Swiss TST 2000 p3

February 19, 2020
Equilateralcombinatorial geometrygeometry

Problem Statement

An equilateral triangle of side 11 is covered by five congruent equilateral triangles of side s<1s < 1 with sides parallel to those of the larger triangle. Show that some four of these smaller triangles also cover the large triangle.