Math Gold Medalist

Lor

2023 AIME II

Problem 12

In $\triangle ABC$ with side lengths $AB = 13,$ $BC = 14,$ and $CA = 15,$ let $M$ be the midpoint of $\overline{BC}.$ Let $P$ be the point on the circumcircle of $\triangle ABC$ such that $M$ is on $\overline{AP}.$ There exists a unique point $Q$ on segment $\overline{AM}$ such that $\angle PBQ = \angle PCQ.$ Then $AQ$ can be written as $\frac{m}{\sqrt{n}},$ where $m$ and $n$ are relatively prime positive integers. Find $m+n.$

Ratio Lemma

Double Sine Law

Double Cosine Law

Congruent Triangles

Median Formula

2 Equal Angles for Using Power

BP/PC=15/13

QB/QC=13/15

BQ=CP

BP=CQ

CQ is parallel to BP

MA=sqrt(148)

MQ=49/sqrt(148)

   Solution