Wolfram Alpha is an interesting search engine because of the unique tasks it can perform. Wolfram Alpha has a function that will walk you through the steps of solving an equation. To use this function, enter your equation then click the “show steps” link that appears in the solution box. You can read more about this function on the Wolfram Alpha blog. If you’re not familiar with Wolfram Alpha, you may want to watch these videos
Some videos: http://www.freetech4teachers.com/2009/10/couple-of-succinct-explanations-of.html
Wolfram Alpha website: http://www.wolframalpha.com/