<PRE><B>Question 457113</B>
9ac/a^2-c^2 - a-c/a+c 
Subtract. Simplify by removing factors of 1.
9ac/a^2-c^2 - a-c/a+c 
Subtract. Simplify by removing factors of 1.
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Factor:
(9ac)/[(a-c)(a+c)]  - (a-c)/(a+c)
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lcd = (a-c)(a+c)
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Rewrite each fraction with the lcd as its deonominator:
(9ac)/lcd - [(a-c)(a-c)]/lcd
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Combine the numerators over the lcd:
[9ac-(a^2-2ac+c^2)]/lcd
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Simplify:
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(-a^2+11ac-c^2)/lcd
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= [-a^2+11ac-c^2)/[a^2-c^2]
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Cheers,
Stan H.
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