Dynamic rhombus

A rhombus is a quadrilateral with all sides equal. (Note that this includes squares---see if you can make one.) The same rhombus is shown in two different positions. Move point B to change the position and size of the rhombus. Move the slider to change the angle BAC.
Part of the textbook Measuring the World: Mathematics for Elementary and Middle School Teachers by Susan Addington and David Dennis. Copyright 2009.