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Cut-the-Knot Action 15!

Author:Tim Brzezinski
Topic:Circumcircle or Circumscribed Circle, Incircle or Inscribed Circle
Creation of this applet was inspired by a tweet from Alexander Bogomolny. How can we formally prove THIS to be true?

Quick (Silent) Demo

New Resources

  • Parallel Lines & Related Angles: Quick Reminders
  • seo tool
  • Parallel Lines and Angles: Thinking Classroom Exploration
  • apec
  • Creating your own GPTs or Gems

Discover Resources

  • Activity 1.7.3 File 1
  • catherine ...
  • Siberio_Period7_Translation
  • การคูณจำนวนเต็ม
  • Activity #12__the Perpendicular Line tool

Discover Topics

  • Geometric Mean
  • Centroid or Barycenter
  • Linear Functions
  • Limits
  • Continuity
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