Posted by Joel on October 26, 2002 at 11:23:02:
In Reply to: Re: geometry posted by Denis Borris on October 26, 2002 at 02:57:52:
: : why do the angles of a triangle add up to 180*?
: You had me stumped for a while...was ready to bs my way with:
: a straight line has 180 degrees, and to make a triangle, you can
: "fold or bend" that straight line, so the triangle HAS to have them
: 180 degrees...but I knew damn well Mr G et al would have put a
: stick in my spokes with: why has a straight line 180 degrees ?!
: Then it came to me; ARE YOU READY?
: A square or rectangle has 4 right angles, so 360 degrees, right?
: Draw a corner to corner diagonal : that splits it in exactly 2 identical
: triangles, right? So each s'got to have 180 degrees...
: How you like them apples, Joel?
That proves that an isosceles right triangle has 180 degrees. You'll have to work a little harder to prove it for all triangles.