Angle Between Reflections of Parallel Rays in Oblique Mirrors
Channel: Saltire Software
Date: 2020-11-24

Given triangle ABC with angle ABC=θ, the images of two parallel rays under reflection in BA and BC meet at angle 2(π-θ)
From this , we can deduce that the intersection of the reflected images lies on the cicumcircle of B,C and the circumcenter of ABC.