MathDB

1

Part of 2004 Turkey MO (2nd round)

Problems(1)

Turkey NMO 2004 P.1, Easy Problem

Source:

12/11/2010
In a triangle △ABC\triangle ABC with∠B>∠C\angle B>\angle C, the altitude, the angle bisector, and the median from AA intersect BCBC at H,LH, L and DD, respectively. Show that ∠HAL=∠DAL\angle HAL=\angle DAL if and only if ∠BAC=90∘\angle BAC=90^{\circ}.
geometryparallelogramtrapezoidrectangleangle bisectorgeometry proposed