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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

  • Nikmati Keunggulan Di Bandar Judi Terpercaya
  • bewijs stelling van Pythagoras
  • Reflection = 180° Rotation about a Line
  • Exploring GeoGebra for the First Time
  • Volume by Disk/Washer around y

Discover Resources

  • Changing b value
  • Exterior Angles of Polygons
  • ggb_prob8_3
  • Rotations Project
  • Vector Components with a 3:4:5 Similar Triangle

Discover Topics

  • Area
  • Tangent Line or Tangent
  • Pie Chart or Circle Chart
  • Circle
  • Scalene Triangles
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