Excel can solve for unknown variables, either for a single cell with Goal Seek or multiple cells with Solver.

Excel can solve equations through several of its mathematical functions, but the single Excel tool that works on the largest variety of equations is the program's Solver Add-in.

In designing the spreadsheet optimizer that is bundled with Microsoft Excel, we and Microsoft made certain choices in designing its user interface, model processing, and solution algorithms for linear ...

Excel Solver employs the generalized reduced gradient algorithm 7; a discussion of the mathematical formalism is beyond the scope of this protocol but can be found elsewhere 8.