Quadrilateral Surprise!

Author:Tim Brzezinski

How would you put this property (dynamically illustrated below) into words? (Applet works best if quadrilateral is kept convex.) How can you formally prove what this applet informally illustrates?

Quick (Silent) Demo

New Resources

Untitled
Monge's Theorem
Trophy (version 2)
רישום חופשי
Constructing an Inscribed Equilateral Triangle + Activities

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Exercise Fig 2.7
bug intersection cercle
Ellipse lab
Tower of Hanoi
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Trapezoid
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Geometry
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