The basic theme of that simplification is to find a common denominator and then simplify the final terms in the numerator and denominator.  It is probably best first reduce the number of solution steps, to do that click on the 'Options' tab and select 'a few steps'.  Next, review the first solution step by clicking on that step and reviewing what is taking place. 

Once a final least common factor has been defined, review the denominator and numerator simplifications.  Notice that the initial expression in the numerator requires a pattern that will become familiar: identify common factors and in that expression '2x' and '3y' are common and easily factored out.... that makes it easier to cancel out 'x' and 'y' terms, leaving a much simpler expression which is simplified by added 'like terms'.