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

bewijs stelling van Pythagoras
Oddly Satisfying Voronoi Diagram
רישום חופשי
အခြေခံ data အခေါ်အဝေါ်များ
Sunny Variations

Discover Resources

Problem 24
Skew Lines Example
Ejercicio 7
Geometry - Perpendicular Bisectors and Circumcenter Theorem
Angle Bisectors

Discover Topics

Linear Regression
Square
Orthocenter
Indefinite Integral
Triangles