



 
Hi Jessica. I've rewritten the starting point: Can you see that b^{2}  25 is a difference of squares? That means the first term is a perfect square, the second term is a perfect square and there is a minus between them. Whenever you see this, you know it factors into the sum of the roots times the difference of the roots: Now that all the denominators are broken into their factors, you can readily find a common denominator by multiplying (b5)(b+5)(b). So the first term needs a b in the denominator, so you multiply it by b/b, the second term needs two factors: b and b5, so multiply by both, top and bottom, and so on. Finally, multiply it out and simplify: I am showing the same answer you were given. Can you find the error you made? Hope this helps,  


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