I have a script installed here - [url removed, login to view] - which will solve equations.
1) Add a limited version of MathQuill - [url removed, login to view] - to allow users to enter the maths.
2) Show Quadratics being solved through factorization if possible and then by the formula if not (currently just uses quadratic formula)
3) Add support for square and cube roots, equations of the form x^3=8 etc
4) Show the solutions of simultaneous equations through standard elimination rather than the current method of gaussian elimination.
5) Allow inequalities to be solved (3x<9 etc)
6) Add more steps in the working out at most stages (I will show you what to add and where)