Area Formulas
for basic shapes

with animated justifications

Area of a Rectangle
Area of a Parallelogram
Area of a Triangle 1.
Area of a Triangle 2. 
Area of a Trapezoid 1.
Area of a Trapezoid 2.
Area of a Circle 1.
Area of a Circle 2.

Other animated pages:
The Pythagorean Theorem, Sine Curve, Cosine Curve.
You may also find some of these in the National Curve Bank as Deposit #17, Deposit #18, and Deposit #85.

Tom Richmond's homepage.

Animations by Bettina Richmond and Tom Richmond.
Updated May 26, 2008.