<PRE><B>Question 387445</B>
(w-1/w-9)-(w+1/w+9)+(w-153/w^2-81) 
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Notice that (w-9)(w+9) = w^2-81
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least common denominator: w^2-81
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Rewrite each fraction with the lcd as its denominator:
[(w-1)(w+9)]/lcd - [(w+1)(w-9)]/lcd + (w-153)/lcd
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Since the denominators are all the same, combine the numerators to get:
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[w^2+8w-9 - [w^2-8w-9] + (w-153)]/lcd
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Simplify the numerator:
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[17w-153]/lcd
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Factor:
[17(w-9)]/[(w-9)(w+9)]
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Cancel to get:
= 17/(w+9)
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Cheers,
Stan H.</PRE>