ISL 2016 G5
Let be the foot of perpendicular from to the Euler line (the line passing through the circumcentre and the orthocentre) of an acute scalene triangle . A circle with centre passes through and , and it intersects sides and at and respectively. Let be the foot of altitude from to , and let be the midpoint of . Prove that the circumcentre of triangle is equidistant from and .
Official text Transcription from NuminaMath olympiads, checked word for word against the official paper. Quoted with source.
Official text: IMO 2016 Shortlist booklet, page 10.
Solutions
Official solution Solution 1 by the IMO Problem Selection Committee
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