2. © 2009, Dr. Jennifer L. Bell, LaGrange High School, LaGrange, GeorgiaActivities from Patty Paper® Geometry by Michael Serra

3. Steps: 1.Draw a circle with the Solo cup. 2.Use your straightedge to draw 2 chords as shown. 3.Label ∠ 1 and ∠ 2 as shown. What do we know about the relationship between ∠ 1 and ∠ 2? How can we prove that with our diagram? 1 2 © 2009, Dr. Jennifer L. Bell, LaGrange High School, LaGrange, GeorgiaActivities from Patty Paper® Geometry by Michael Serra

4. Steps: 5.Fold the circle where the sides of ∠ 1 meet the side of ∠ 2. What do you notice? 1 2 1 2 © 2009, Dr. Jennifer L. Bell, LaGrange High School, LaGrange, GeorgiaActivities from Patty Paper® Geometry by Michael Serra

5. Steps: 6. Draw a chord for each arc. 7.Compare the chord lengths. What do you notice? 1 2 © 2009, Dr. Jennifer L. Bell, LaGrange High School, LaGrange, GeorgiaActivities from Patty Paper® Geometry by Michael Serra

7. Steps: 1.Draw a circle with the Solo cup. 2.Use your straightedge to draw 2 chords on your circle. 3.Fold to find the perpendicular bisector. 4.Place the corner of another piece paper at the angle formed between the chord and the perpendicular bisector. What do you notice?

8. © 2009, Dr. Jennifer L. Bell, LaGrange High School, LaGrange, GeorgiaActivities from Patty Paper® Geometry by Michael Serra

9. Steps: 1.Draw a circle with the Solo cup. 2.Fold to find a central angle. 3.Place another patty paper on top and copy the angle.

10. Steps: 4.Copy this angle in the original circle so that you have 2 central angles that are not vertical. 5.Compare the lengths of the arcs by folding. Are they congruent? 6.Draw a chord for each arc. 7.Compare the chord lengths by folding. © 2009, Dr. Jennifer L. Bell, LaGrange High School, LaGrange, GeorgiaActivities from Patty Paper® Geometry by Michael Serra