you could expand it as follows :
Let's first expand . This is done by distributing :
Now apply the distributive law again :
Does this help ?
PS : since I'm in a good mood I'll give you a nice website to check your results (if you don't know it already). It is called Wolfram Alpha, and you can type in what you want it to do (like "expand/factor/simplify [expression]", "solve [equation]"), and it will most likely do it correctly.