Two not necessarily equal non-intersecting wooden disks, one gray and one black, are glued to a plane. An infinite angle with one gray side and one black side can be moved along the plane so that the disks remain outside the angle, while the colored sides of the angle are tangent to the disks of the same color (the tangency points are not the vertices). Prove that it is possible to draw a ray in the angle, starting from the vertex of the angle and such that no matter how the angle is positioned, the ray passes through some fixed point of the plane. (Egor Bakaev, Ilya Bogdanov, Pavel Kozhevnikov, Vladimir Rastorguev) (Junior version here)
HIDE: note There was a mistake in the text of the problem 3, we publish here the correct version. The solutions were estimated according to the text published originally.Problem
Source: Tournament of Towns, Senior A-Level , Spring 2019 p3
Tags: geometry, fixed, angle bisector, Fixed point, circles, Coloring, Kvant