MathDB
Maybe a P1

Source: Iran MO 2023 3rd round , geometry exam P2

August 23, 2023
geometry

Problem Statement

In triangle △ABC\triangle ABC , MM is the midpoint of arc (BAC)(BAC) and NN is the antipode of AA in (ABC)(ABC). The line through BB perpendicular to AMAM , intersects AM,(ABC)AM , (ABC) at D,PD,P respectively and a line through DD perpendicular to ACAC , intersects BC,ACBC,AC at F,EF,E respectively. Prove that PE,MF,NDPE,MF,ND are concurrent.
Back to ProblemsView on AoPS