Deja Vu all over again!

[chris]

On Tue, 2011-07-05 at 15:58 +0800, Goh Lip wrote:
> On 07/05/2011 03:44 PM, Goh Lip wrote:
> 
> >
> > Isn't this better?.
> >
> > 'Tis all a Chequer-board of Nights and Days
> > Where Destiny with Men for Pieces plays;
> > Hither and thither moves, and mates, and slays,
> > And one by one back in the closet lays.
> > ------- Omar Khayyam
> 
> 
> But his best work,
> 
> (x +c)(a −x) = (y +b)2
> 
> ;)
> 
> 
where the value of x is ?