In this investigation, you will explore the sum of the measures of the interior angles of triangles, quadrilaterals and other polygons using rotations of 180° about a midpoint of a side.
After you complete the activity, try another shape. Do your results stay the same? Explain.
If you experience difficulties running this activity in your browser, please see the browser help file for advice.
© 2006 Applet written by S. Keller, Department of Mathematics, Michigan State University