tangent at intersection of diagonals of a cyclic ABD parallel to a side
Source: 2006 Oral Moscow Geometry Olympiad grades 8-9 p1
October 17, 2020
geometrytangentcyclic quadrilateral
Problem Statement
The diagonals of the inscribed quadrangle intersect at point . Prove that the tangent at point to the circle circumscribed around the triangle is parallel to .(A Zaslavsky)