## Mirror Tool

9-12
Standards:
Math Content:
Geometry

Use this tool to investigate symmetry. You can rotate, flip, or reflect a figure across a line.

Click on any shape to bring that shape into the work area.

 When the arrow is active, move a shape within the work area by dragging it. Deactivate the flip, rotate, and erase butons by clicking on the arrow. The green line represents the edge of a mirror. Move the line by dragging the two green dots. To reflect an object across the green line, press the reflect button; to undo the reflection, press this button again. To rotate a shape, activate the rotate button, and then click on a shape. To flip a shape, activate the flip button, and then click on a shape. To erase a shape, activate the erase button, and then click on a shape.
Click on one of the figures from the left column to place it on the drawing surface. Describe the figure. Does is have reflective symmetry? Does it have any other types of symmetry?

Move the green reflection line, then press the reflect button. What happens to the figure? Drag the green line around the screen while the reflect button is selected. Describe what happens.

Can you place the green line so that the image and its reflection look exactly like the original figure? For which figures is this impossible?