JBMO-SL 2015 G5
ROU
Let be an acute triangle with . The incircle of the triangle touches the sides and at and , respectively. The perpendicular line erected at onto meets at , and similarly, the perpendicular line erected at onto meets at . The line meets again in , and the line meets again at . Prove that .

Dataset text NuminaMath olympiads. Quoted with source.
Solutions
No solution is on olymmath yet. Official and human solutions come first when they arrive. AI solutions come after them, with a label.