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Guest Message by DevFuse

# Quadrilateral, spheres, tangency, and proofs oh my!

Best Answer bonanova, 07 March 2013 - 08:46 AM

Spoiler for nice problem

Go to the full post

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Posted 05 March 2013 - 02:23 AM

A quadrilateral is given in space, such that its edges are tangent to a sphere.  Prove that all the points of tangency lie in one plane.

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### #2 bonanova

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Posted 07 March 2013 - 08:46 AM   Best Answer

Spoiler for nice problem

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Vidi vici veni.

### #3 k-man

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Posted 07 March 2013 - 10:03 PM

Spoiler for nice problem

That's an interesting approach to solving a problem, but I guess what remains to be proven is

Spoiler for

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### #4 bonanova

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Posted 08 March 2013 - 03:01 AM

Spoiler for nice problem

That's an interesting approach to solving a problem, but I guess what remains to be proven is

Spoiler for

Spoiler for Here is the process

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Vidi vici veni.

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