Talk:Pappus's Hexagon Theorem

There is an interesting discussion of Pappus's Theorem here:

http://www.cut-the-knot.org/pythagoras/Pappus.shtml

The page gives an elementary proof based on Menelaus's Theorem. The proof relies on an arrangement where $aB$ is not parallel to $bC$, using the notation of this page. I notice that your diagram makes them parallel (deliberately?).

No I didn't -- and in fact they're not parallel. --prime mover (talk) 12:21, 1 November 2023 (UTC)

He also makes an argument from projective geometry as to why this is not fatal. That part is beyond me to explain properly. If you are interested in this approach I will work it up, unless you judge that it would be unsatisfactory in principle. --Telliott99 (talk) 11:13, 1 November 2023 (UTC)

As it's a theorem in projective geometry, it makes sense to leave that aspect of it alone until we've covered the subject adequately. --prime mover (talk) 12:21, 1 November 2023 (UTC)