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Topic:
Geometry Problem
Replies:
17
Last Post:
Feb 20, 2008 10:04 AM




Re: Geometry Problem
Posted:
Feb 18, 2008 11:55 PM


In article <MPG.22243347aced4a5d9899a1@news.cc.tut.fi>, Kaba <none@here.com> wrote:
> > Hi all, > > > > I need help with this problem: > > > > http://img180.imageshack.us/img180/8286/20080218181526nq7.gif > > > > The angle to find is ECD. > > > > The matter is solving it without trigonometric functions. > > With trigonometry or by drawing it you can see that the angle to find > > is 20° (sessagesimal) but I can't find it using a simple solution > > (properties of triangles, the parallel postulate and so on). > > > > Can you solve it? > > Interesting problem, couldn't solve it either. I get 4 unknowns but only > 3 linearly independent equations.
consider triangles BDC and ECD and their angles as well as intersecting and straight lines. Pretty easy no real equations just bookkeeping....



