MathDB
tangent circumcircles result in tangent circumcircles

Source: 2002 Estonia National Olympiad Final Round grade 12 p4

March 14, 2020
geometrycircumcircletangent circles

Problem Statement

A convex quadrilateral ABCDABCD is inscribed in a circle ω\omega. The rays ADAD and BCBC meet in point KK and the rays ABAB and DCDC meet in LL. Prove that the circumcircle of triangle AKLAKL is tangent to ω\omega if and only if so is the circumcircle of triangle CKLCKL.
Back to ProblemsView on AoPS