(a+b)(a-b)=(a*a)-(b*b). (b*b)=(ab). So (a+b)(a-b)=(ab)-(bb). This can be factorized (right word?): b(a-b). That was that term, but as you, I can't see how he get's to this sollution. I think he puts b(a-b)=0, and throws the B over. But 2a=a only if a=b=0.

This reminds me of when someone in my class figured out that santa can't possiblly exist, useing sience. It's the minus of being a nature scientist <img src="/ubbthreads/images/graemlins/rolleyes.gif" alt="" />.

�bereil


Brain: an apparatus with which we think we think.

Ambrose Bierce