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Guest Message by DevFuse

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

Started by BMAD, Mar 05 2013 02:23 AM

3 replies to this topic

### #1

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.

### #2

Posted 07 March 2013 - 08:46 AM Best Answer

Spoiler for nice problem

*Vidi vici veni.*

### #3

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

### #4

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

*Vidi vici veni.*

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