I'm in a college algebra class and we're getting started with factoring. I'm going through most of them just fine but I'm stuck on this:

2(x+1)(x-3)^2 - 3(x+1)^2(x-3)

I'm guessing I multiply everything out, and I did, and got to this point:

-x^2(x+7) + 3(7x+9)

Is that it? Is it even right? I'd appreciate some help Thanks!!