MathDB
every very distinguished pentagon has an axis of symmetry

Source: Austrian Regional Competition For Advanced Students 2013, p4

February 19, 2020
equal segmentsequal anglespentagongeometrysymmetry

Problem Statement

We call a pentagon distinguished if either all side lengths or all angles are equal. We call it very distinguished if in addition two of the other parts are equal. i.e. 55 sides and 22 angles or 22 sides and 55 angles.Show that every very distinguished pentagon has an axis of symmetry.