ISL 2020 G2
Let be a convex quadrilateral. Suppose that is a point in the interior of such that The internal bisectors of angles and meet at a point inside the triangle . Prove that . (Poland)
Dataset text NuminaMath olympiads. Quoted with source.
Official text: IMO 2020 Shortlist booklet, page 10.
Solutions
Official solution Solution 1 by the IMO Problem Selection Committee
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