ISL 2020 G5
Let be a cyclic quadrilateral with no two sides parallel. Let , and be points lying on sides , and , respectively, such that is a rhombus with and . Let , and be the incircles of triangles , , and , respectively. Prove that the internal common tangents to and and the internal common tangents to and are concurrent. (Poland)
Official text Transcription from NuminaMath olympiads, checked word for word against the official paper. 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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