The choice for method is "under the hood" using doyourmath.com but is more configurable using Algebrator.  As shown in the attached image for the current equation you entered, the solution is obtained by factoring.  Clicking on a particular solution step affords the logic which is employed.  Notice also that I used the 'Options' tab to choose 'a few steps' in order to provide a more succinct solution (sometimes additional solution steps can lead to a bit of confusion, but sometimes additional solution steps are very helpful!). 

The desktop version of Algebrator can be reviewed through the free trial:

Windows: http://www.softmath.com/tr/alg51win-tr-en.exe

Mac: http://www.softmath.com/tr/alg51mac-tr-en.dmg