A few days ago I posted a question about solving an equation that is passed as a string (with a single variable, x). I have written bug-free code to take an expression and insert * when needed and move everything to the left side of the equation. 
 2(4x-8)+3x=11x+1-9
2(4*x-8)+3*x=11*x+1-9
(2(4*x-8)+3*x)-(11*x+1-9)
(2*(4*x-8)+3*x)-(11*x+1-9)

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I then wrote code to turn the string into Reverse Polish Notation. So, my output so far is: 24x*8-*3x*+11x*1+9-- However, after writing this, I realized that I am stuck... While I started converting to RPN, I thought it would make things much easier, but at this point, I'm completely lost.

EDIT: Thank for some awesome advice and answers! I've learned a lot, and translated RPN strings into solved equations! Clarification for those that were wondering: I was asking how to take a RPN string that contained variables, and solve for that variable.

In reply to RPN Question by nat47

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