Problem

Source: 2022 Yasinsky Geometry Olympiad X-XI p1 , Ukraine

Tags: geometry, angles, median



In the triangle $ABC$, the median $AM$ is extended to the intersection with the circumscribed circle at point $D$. It is known that $AB = 2AM$ and $AD = 4AM$. Find the angles of the triangle $ABC$. (Gryhoriy Filippovskyi)