MathNet 2010 — Part 02 Question 71

The points $M$ and $N$ are chosen on the bisector $AL$ of a triangle $ABC$ such that $\angle ABM = \angle ACN = 23^\circ$. $X$ is a point inside the triangle such that $BX = CX$ and $\angle BXC = 2\angle BML$. Find $\angle MXN$.