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Topic: Classifying quads visually
Replies: 2   Last Post: Nov 1, 2008 11:31 AM

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Joseph Malkevitch

Posts: 12
Registered: 6/22/06
Re: Classifying quads visually
Posted: Nov 1, 2008 11:31 AM
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Dear Colleagues,

Another interesting approach to classifying quadrilaterals appears in the paper by Branko Grünbaum:

The Angle-side Reciprocity of Quadrangles in Geombinatorics, Volume IV, 1995, pg. 115-118.

In his system Grünbaum finds 20 different kinds of plane,convex quadrilaterals, many of them not having names in other approaches.

Best wishes,


Joseph Malkevitch
Department of Mathematics
York College (CUNY)
Jamaica, New York 11451

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