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




Re: Geometry Problem
Posted:
Feb 20, 2008 7:56 AM


I.M. Soloveichik wrote : > There is not enough information unless that angle at D which looks like it is > 90 is supposed to be 90in that case the angle x is 40 degrees.
A constructive proof that there is enough information to get the *angles* :
Construct on a given base EB the 4 rays with given angles, they intersect into C and D. Starting from a different base EB gives just a simiular figure, hence with all same angles.
And of course the "9O° looking" angle is ... not 90°, but 110°.
Regards.
 Philippe C., mail : chephip+news@free.fr site : http://chephip.free.fr/ (recreational mathematics)



