Wolfram Research
Wolfram Math World: Math World: Geometric Construction
Offers an explanation of what a geometric construction is and what some of the tools are that are used for it, including the traditional straightedge and compass. The site explains how to construct various polygons inscribed within a...
Math Is Fun
Math Is Fun: Constructing a Triangle With 3 Known Sides
Students learn how to construct a triangle with three known sides using a straightedge and a compass. Includes an animated demonstration.