Find the difference.

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BonafideLove95 BonafideLove95
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Find the difference.

Find the difference. 
9/x+2  minus  8/x-7
AlgebraHouse AlgebraHouse
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Re: Find the difference.

9/x+2  minus  8/x-7

When adding and subtracting fractions, you need to get the least common denominator.
When deciding on the least common denominator, you need one of each term.

9/(x + 2) - 8/(x - 7) {the least common denominator is (x + 2)(x - 7)}
= 9(x - 7) / (x + 2)(x - 7) - 8(x + 2) / (x + 2)(x - 7) {got the least common denominator}
= 9x - 63 / (x + 2)(x - 7) - 8x + 16 / (x + 2)(x - 7) {used distributive property in numerators}
 
x - 79
--------------
 {combined numerators and put over common denominator (watch signs)}
(x + 2)(x - 7)

- Algebra House