MathDB

4

Part of 1996 Canada National Olympiad

Problems(1)

Find the angle of an isosceles triangle with BC = BD + AD

Source: Canada 1996; Moroccan correspendance program 2005(?) (Problem 4) (posted by Erdos)

3/4/2006
Let triangle ABCABC be an isosceles triangle with AB=ACAB = AC. Suppose that the angle bisector of its angle ∠B\angle B meets the side ACAC at a point DD and that BC=BD+ADBC = BD+AD. Determine ∠A\angle A.
trigonometrygeometryangle bisectorgeometry unsolved