i need help with a divide problem

Question

anonymous · Answer

What is the problem?

anonymous · Answer

what is the division problem?

anonymous · Answer

|dw:1345690087031:dw|

anonymous · Answer

First, you need to factorize the first fraction on the left. Can you do that?

anonymous · Answer

I need help with  that.

phi · Answer

There are 2 things you need to know to do this problem:
1)  dividing can be replaced by "inverting and multiplying"
2)  how to factor the polynomials


For (1), that means  $ 4 \div 2$ can be replaced by $ 4\cdot \frac{1}{2} $
You "flip" the second number, and then multiply. 
That means for your problem, flip the 2nd fraction, and multiply 

Now the 2nd step:  factor both the top and bottom

phi · Answer

do you know that the "difference of two squares"  (a^2 - b^2) = (a-b)(a+b)
do you see the bottom of the 1st fraction matches this pattern?

phi · Answer

you can write 
$$ x^2 -49= (x^2-7^2) $$