Talk:09-240/Classnotes for Thursday September 10

I can't get the "alignat" tags working correctly. They're what I would prefer to use for systems of equations, instead of having each individual equation enclosed in "math" tags. They seem to work fine on Wikipedia (see http://en.wikipedia.org/w/index.php?title=System_of_linear_equations&action=edit).

--- Unfortunately the problem will probably not get resolved during term - I think it comes because I'm using an old version of MediaWiki, and I will not upgrade during classtime. Sorry, Dror.