It is a consequence of Euclids's parallel postulate.
http://wiki.answers.com/Q/Why_does_a_triangles_ang...

4/17/96 at 19:16:32 From: Anonymous Subject: Geometry, angles in a triangle Hi! We were wondering why all the angles in a triangle add up to 180 degrees. Several of us are trying
http://mathforum.org/library/drmath/view/57727.htm...

The maximum angle is 360Â°.This is the angle all the way
http://www.chacha.com/question/whydoalltheangl...

A square sandwich, that you cut in half on the diagonal. Before it is cut, each corner of the square sandwich is 90 degrees. When it is cut, the corner is split in half, and half
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