## Thursday, November 3, 2011

### Area of a Trapezoid

Move point A to change the shape of the trapezoid.  Then move slider $\alpha$ to the extreme right to rotate the trapezoid.

This is a Java Applet created using GeoGebra from www.geogebra.org - it looks like you don't have Java installed, please go to www.java.com

1.) What kind of quadrilateral  is formed when $\alpha$ equals 180 degrees? Justify your answer.
2.) What is the relationship between the area of trapezoid ABCD and the area of the quadrilateral formed in 1?
3.) Using the quadrilateral formed in 1, find the area of the trapezoid. Hint: Use $b_1, b_2$ and $h$.