It has become obvious that the Shapes category was in way over its head with all sorts of geometrical problems. So, the hard-core Geometry problems will now reside here, where they will fit in much better.
In Obtuse triangle from equilateral triangle we were asked to construct an 120-degree obtuse triangle from segments of an equilateral triangle ABC and an arbitrary cevian BD.
What is the area of this 120-degree obtuse triangle expressed in terms of the lengths of side AB and cevian BD?
Latest: 
