ISL 2012 G5
Let be a triangle with , and let be the foot of the altitude from . Choose a point in the interior of the segment , and let be the points on the segments for which and respectively. Denote by the intersection of and . Show that .
Official text Transcription from NuminaMath olympiads, checked word for word against the official paper. Quoted with source.
Official text: IMO 2012 Shortlist booklet, page 6.
Solutions
Official solution Solution 1 by the IMO Problem Selection Committee
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