Regular triangles are built on the sides of the triangle $ABC$. It turned out that their vertices form a regular triangle. Is the original triangle regular also?
Source: Sharygin 2006 IX-XI CR 16
Tags: geometry, Equilateral, Equilateral Triangle
Regular triangles are built on the sides of the triangle $ABC$. It turned out that their vertices form a regular triangle. Is the original triangle regular also?