Mathtoys is an online tool for helping you solve algebra problems step by step. You decide what step to do next, and it takes care of the details.
Mathtoys proves everything it does starting from basic laws of numbers and reasoning. This means you cannot do an incorrect step. You may not get a solution, or perhaps not exactly the solution you were looking for, but each step and each result will be mathematically correct.
Mathtoys does its reasoning using the Prooftoys proof assistant, slightly extended for math education. Both Prooftoys and Mathtoys are open source software, which means they are available for anyone to use, learn from, or improve, with complete access to the source code. For more information about all of this check out the Prooftoys web site.
So far Mathtoys has learned definitions and useful steps for solving equations and simplifying expressions in basic algebra. It comes with a few predefined problems, or you can enter your own. Click on a step in your problem or any expression to see options using your selection in the next step. You can remove steps you don't like at any time, and try again.
Try it for yourself: