SUBJECT>Re: An Algebra puzzle for your amusement. POSTER>Taz EMAIL>rmaxey@worldnet.att.net DATE>March 24, 1997 at 07:37:37 EMAILNOTICES>no PREVIOUS>1403 NEXT>1408 LINKNAME> LINKURL>

As a mathematician by education, I'm not sure I should spoil it for everyone else, but here goes:

A=B => A-B=0,

You can't divide by 0, so the transition from step 4 to step 5 is invalid.
QED

Taz