Let ABC be an acute triangle. Let D be a point on the line parallel to AC that passes through B, such that ∠BDC=2∠BAC as well as such that ABDC is a convex quadrilateral. Show that BD+DC=AC.
Source: KAMO 2022 Grade 9 P2
Tags: geometry, rectangle
Let ABC be an acute triangle. Let D be a point on the line parallel to AC that passes through B, such that ∠BDC=2∠BAC as well as such that ABDC is a convex quadrilateral. Show that BD+DC=AC.