Shape 

Copyright David & Cynthia Thomas, 2009

Symmetry--Directed Activity: Point of Symmetry

Focus

Point of symmetry

Technologies

Protractor and The Geometers Sketchpad and model 4_Points.gsp

Background

Figure 4.3: Points of Symmetry

Tasks

For each object in Figure 4.3

· Find a point of symmetry.

· Select two vertices that are “images” of each other relative to a point of symmetry and measure the angle determined by each vertex and the point of symmetry. 

· Repeat using The Geometers Sketchpad and model 4_Points.gsp

· Formulate and test a conjecture concerning all such angles.