Wednesday, January  29, 2014
  Class #3

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• Discussion of course details:
  
• Any questions on course description
  
• Correction of Dates.
  
• Reminder to read Flatland.
• Look over reading and assignments
• Discussed assignment for next week - submit by noon, Friday- Feb.7. Interview Report.
• Card tricks with magic deck. Question: How does this work?
  

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Measurement and the Pythagorean Theorem (PT)

a² + b² = c²

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Show video on PT.
Outline:
Area of triangles = 1/2 bh
Area of parallelogram= bh
Scaling: a linear scale change of r gives area change of factor r².
3 questions: running, moat, wind power...
Proof of the PT: Similar right triangles: c = a² /c + b² /c 

• Do Pythagorean Activity Sheet
• Virtual Manipulative for PT
• Discuss Pythagorean Theorem and proofs.
• Over 30 proofs of the Pythagorean theorem!
• Many Java Applets that visualize proofs of the Pythagorean Theorem

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