Subj:     The Vanishing Area Paradox (S461b) 
          by Martin Gardner 
          From: PlanetPerplex.com on 11/20/2005
          (See 'Two triangles Problem' in ILLUSIONS2)

Source: http://www.planetperplex.com/en/sliding_puzzles.html

Cut out the parts of the first rectangle and build the
second rectangle.  Where did the red area come from?


 
 
 

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