Cyclic quadrilateral with diagonals question
Source: IrMO 2022
May 10, 2022
geometrycirclescyclic quadrilateral
Problem Statement
7. The four Vertices of a quadrilateral ABCD lie on the circle with diameter AB. The diagonals of ABCD intersect at E, and the lines AD and BC intersect at F. Line FE meets AB at K and line DK meets the circle again at L.Prove that CL is perpendicular to AB.