<PRE><B>Question 522695</B>
(-1)/(b^2-4)}}}-{{{(-2)/(b^2-4b-12) 
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Factor where you can:
[-1/(b-2)(b+2)] - [-2/(b-6)(b+2)]
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lcd = (b-2)(b+2)(b-6)
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Rewrite each fraction with the lcd as its denominator:
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[-(b-6)]/lcd - (-2(b+2)]/lcd
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Combine the numerators over the lcd:
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[-b+6-2b-4]/lcd
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Simplify:
[-3b+2]/[(b^2-4)(b-6)]
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Cheers,
Stan H.
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