MathNet 2025-part-02 — 186 problems (EN–VI) Question 59

Let $ABC$ be an isosceles triangle with $AB = AC$ and $\angle BAC = 20^\circ$. Points $X$ and $Y$ are taken on side $AC$ such that $AX = YC = BC$. Find $\angle XBY$.
Mihaela Berindeanu