Home | Geometry | Quadrilaterals | Recommended Investigations | Mystery Quadrilaterals

Mystery Quadrilaterals

Some quadrilaterals have special names because they have some special properties. For example, a rectangle is any quadrilateral with four right angles. Alternately, a rectangle is a parallelogram with 1 right angle (Can you explain why?) A square is "more special" than a rectangle because it has four right angles and four equal sides (so a square is a special rectangle.)

Each of the Geometer's Sketchpad files below contains a different quadrilateral. Your goal is to use your knowledge about quadrilateral properties to determine the MOST specific name of each quadrilateral.

Be careful! All of the quadrilaterals will look like squares, but only one of them will actually be a square.

Justify each of your responses by including properties of the quadrilateral that make it unique.

 Related External Resources

Investigating Properties
In this activity, we'll construct a demonstration sketch which could be used by middle school students to investigate the properties of quadrilaterals.

Submit your idea for an investigation to InterMath.