This lesson focuses on wallpaper groups. While there are infinitely many possible patterns, they all have one of just 17 different symmetry groups. These are called the Wallpaper Groups. Every wallpaper group is defined by a combination...

This task uses GeoGebra software, which can be freely downloaded, to explore what happens to the line segments and angles of a triangle when it is reflected, rotated, and translated. Includes printable task sheet for students and a...

Find a clear explanation of similar figures. Discusses how they can be transformed through a sequence of rotations, reflections, translations, and dilations. Explanations are supported with illustrated examples.

Reflect any point, line segment, triangle, or any other figure over one or two lines using this dynamic applet. Points and lines are entered by point-and-click rather than by typing equations or ordered pairs. A very neat exercise to...

In this task, seven pennies are placed in a circle so that they are all touching one in the center and their neighbors. Students are asked to find as many rigid motions of the plane as they can which are symmetries of this configuration...