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Topic: circumference in degrees of a triangle
Replies: 10   Last Post: Nov 22, 2003 11:36 PM

 Messages: [ Previous | Next ]
 me@talmanl1.mscd.edu Posts: 1,815 Registered: 12/6/04
Re: circumference in degrees of a triangle
Posted: Nov 22, 2003 11:36 PM

Jim Totten wrote:

> Here's a question:
> Can you, leaving your Parallel Postulate at home, and going for a walk
> around a triangle, PROVE that its interior angles add to 180?

No--and neither can anyone else--unless you allow some equivalent of the
Parallel Postulate. The condition that the sum of the interior angles
of some triangle be 180 degrees is itself an equivalent of the Parallel
Postulate.

--Lou Talman
Department of Mathematical & Computer Sciences
Metropolitan State College of Denver

Date Subject Author
4/2/02 jim coulter
4/2/02 Tom Johnson
4/2/02 Walter Whiteley
4/2/02 Guy Brandenburg
5/2/02 Katie
5/2/02 Guy Brandenburg
4/2/02 Tom Johnson
11/22/03 Yogi
11/19/03 giovanni
11/22/03 Steve Earth
11/22/03 me@talmanl1.mscd.edu