Virtual Nerd
Virtual Nerd: Construct Equilateral Triangle and Square Inscribed in a Circle
Two videos on geometric constructions. One explains how to construct an equilateral triangle using a ruler and compass. The second describes how to draw a square using a compass and a straightedge.
Math Mammoth
Math Mammoth: How to Draw a Right Angle (Perpendicular Line) and a Rectangle
Demonstrates how to draw a right angle and a rectangle. [6:21]