Texas Instruments
Texas Instruments: Using the Equation Solver to Find a Solution
In this tutorial, you will see how to use the Equation Solver (under the MATH) key to find the value of a missing variable in an equation.
Wyzant
Wyzant: Equation Calculator
Students can input an equation and have the site solve it for them, complete with steps shown and explanations given along the way. Equations must be simple, first- or second-degree with only one variable. A quick list of rules to follow...