ISL 2015 G5
Let be a triangle with . Let , and be the midpoints of the sides , and , respectively. A circle passing through and tangent to at meets the segments and at and , respectively. The points and are symmetric to and about and , respectively. The line meets and at and , respectively. The line meets again at . Prove that . (El Salvador)
Dataset text NuminaMath olympiads. Quoted with source.
Official text: IMO 2015 Shortlist booklet, page 7.
Solutions
Official solution Solution 1 by the IMO Problem Selection Committee
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