MathDB
\sqrt{2}(BC-BA)=AC prove that BD is tangent to circumcircle

Source: 239 2017 S6

May 22, 2020
geometryangle bisectorcircumcircle

Problem Statement

Given a circumscribed quadrilateral ABCDABCD in which 2(BC−BA)=AC.\sqrt{2}(BC-BA)=AC. Let XX be the midpoint of ACAC and YY a point on the angle bisector of BB such that XDXD is the angle bisector of BXYBXY. Prove that BDBD is tangent to the circumcircle of DXYDXY.
Back to ProblemsView on AoPS