An interactive applet and associated web page that demonstrate the dilation transformation. The applet shows a rectangle and its dilated image. The user can control the scale factor with a slider control and move a point representing the center of dilation.

The applet can be printed as it appears on the screen to make handouts.

The web page has a full description of the concept of dilation, a worked example and instruction on how to construct a dilation on paper.

Applet can be enlarged to full screen size for use with a classroom projector. After use in the classroom, student can access it again from any web browser at home or in the library with no login required.

This resource is a component of the Math Open Reference Interactive Geometry textbook project at http://www.mathopenref.com.