Do you know where your variables are?  
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Re: solving system of equations with complex expressionsby bluescreen (Friar) 
on Oct 24, 2011 at 21:31 UTC ( #933485=note: print w/ replies, xml )  Need Help?? 
Hi, how do you pass from 2x1+3x27x3+7x5 = 7 to [7,2,3,7,0,7] also the first equation seems to be wrong given you have 22 = 7. Then you show an equation with variables. I'm not clear what are you looking for: a symbolic evaluator? an equation parser? both? Maybe if you explain your problem domain a little bit more people will be able to help you better
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