The first problem is easy, once you notice that

So,

Then multiply the top and bottom of the left hand fraction by (x+4)^2 and the denominators will be the same (1*right hand denominator obviously = right hand denominator, and then balance by multiplying on top)

::edit::

I should have started with this, really. Your method of finding LCD differs from mine, but i didn't notice straight away. Mine works without fail (i think) and is a little simpler (or perhaps just seems that way because im used to it). Here it is:

"Cross multiply". That is, multiply the right fraction by the left denominator, and the left fraction by the right denominator:

Eg

Try this for your second problem. The answer is below, i don't know how to change the colour so that you cant see it until its highlighted. Don't look until you give it a go.

So for your second problem

cross multiply

And simplify to a final answer