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MathNet 2024-part-02 — 168 problems (EN–VI) Question 155

Math Olympiad Vault · MathNet 2024-part-02 — 168 problems (EN–VI)

Question 155

Let $ABC$ be a triangle with incentre $I$, and let $\Omega$ be the circumcircle of triangle $BIC$. Let $K$ be a point in the interior of segment $BC$ such that $\angle BAK \lt \angle KAC$. The angle bisector of $\angle BKA$ intersects $\Omega$ at points $W$ and $X$ such that $A$ and $W$ lie on the same side of $BC$, and the angle bisector of $\angle CKA$ intersects $\Omega$ at points $Y$ and $Z$ such that $A$ and $Y$ lie on the same side of $BC$.
Prove that $\angle WAY = \angle ZAX$.