AD = CD wanted, tangents to circumcircle (2011 Kyiv City MO 9.4.1)
Source:
July 14, 2020
geometrycircumcircleTangentsequal segments
Problem Statement
The triangle is inscribed in a circle. At points and are tangents to this circle, which intersect at point . A line drawn through the point parallel to the side intersects the side at the point . Prove that .