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Topic: Lines in the plane
Replies: 7   Last Post: Apr 27, 2001 5:21 PM

 Messages: [ Previous | Next ]
 S.K.Mody Posts: 31 Registered: 12/13/04
Re: Lines in the plane
Posted: Apr 26, 2001 7:28 PM

"Mike Schubert" <mikeschub2@iol.com> wrote in message
news://yifcfwkp2kcn@forum.mathforum.com...
> How it can be proved that for n>=3, n distinct points in the plane,
> not all on a single line, determine at least n distinct lines ?
>

Suppose that exactly k of the points lie on the same line
for some k ( 2 <= k < n ). Then each of the remaining
n - k points can be paired with each of these points leading
to (n - k)*k distinct lines. Along with the first line this leads
to 1 + (n-k)*k lines which is >= n for n >= 3.

Regards,
S.K.Mody.

Date Subject Author
4/26/01 Mike Schubert
4/26/01 Randy Poe
4/26/01 Chris Thompson
4/26/01 clio
4/26/01 S.K.Mody
4/27/01 S.K.Mody
4/27/01 Ahmed Fares
4/27/01 S.K.Mody