Monday, February 3, 2014
Class #4

Reminder to read Flatland.
Look over reading and assignments

Dissection Puzzles and Polygons

Tangram Introduction

Use all seven Chinese puzzle pieces to make shapes and solve problems.
Tangram Activity

Use tangram plastic sets.

More on the Pythagorean Theorem (PT)

Pythagorean Theorem Triangle with Squares on
Sides

a²+ b²= c²

Review Pythagorean Activity Sheet: What was needed to "prove" the PT?

Virtual Manipulative for PT
Over 30 proofs of the Pythagorean theorem!
Many Java Applets that visualize proofs of the Pythagorean Theorem

Should we believe these dissection proofs?

Curry's Paradox: How Is It Possible?

Other visual tricks ... so why should we believe Pythagoras?

Discuss Pythagorean Theorem and proofs.

Theme Question: Who first showed the earth was a sphere or shaped like a sphere?

Question 1. How can one distinguish the sphere from a plane (Flatland) based solely on experiences on the surface?

Question 2. How can one distinguish the sphere from a torus based solely on experiences on the surface?