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

Single-variable equations are among the easiest to construct when using this tool. Use the Equation Editor to insert an equation into any cell in your Excel worksheet.

Before LAMBDA was introduced to Excel, you'd need to know how to use VBA or macros to create your own function. However, today, Excel's LAMBDA tool lets you do this using familiar Excel language ...

How to Use Variables in Excel. Knowing how to use Excel's variables gives you the ability to make your formulas – and by extension the spreadsheets containing those formulas – much easier to ...