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Having trouble with one of my math homework problems. I need to find the least common denominator (LCD) to solve the problem. I'm not sure how to figure this out one. Thanks in advance.

$ \frac{3}{j^2+6j} + \frac{2j}{j+6} - \frac{2}{3j} .$

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    Actually, you don't need to find the *least* common denominator to solve the problem: all you need is *a* common denominator, and the product of the denominators works fine. Of course, this means that you'll probably have to do some simplification at the end but it is much simpler to start.2011-09-14

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Hint: First try finding the LCD of some integers. For example, evaluate $\frac{3}{4} + \frac{7}{10} + \frac{13}{25}$ and be very conscious of how you're doing it when you get a common denominator. Next try adding these: $\frac{1}{x^2} + \frac{1}{x}$ and $\frac{1}{x+3} + \frac{1}{x^2-9}$ It's the same thing each time, but you need to use a bit of algebra. Now try your homework problem. Good luck!

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Hint: The denominator $j^2 + 6j$ factors as $j(j + 6)$. Now, look at all the factors that appear in the various denominators: $ j, j + 6, 3. $ So, a good common denominator might be $3j(j+6)$. How can you make all the fractions have this denominator?