33. The Solo Compass - 1. Add two segments

Every operation that can be carried out with a straightedge and compass can be done with a compass alone.

Notes:

• d²=b² + 2h² : http://www.geogebratube.org/material/show/id/31406 (The diagonals of a trapezoid. In this problem the trapezoid is isosceles and the base is twice as long as the top.)