Question 192851
(2 over b-3 ) - (7 over b^2-3b)
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2/(b-3) - 7/(b(b-3))

lcd = b(b-3)

= [2b]/lcd - 7/lcd

= [2b - 7]/lcd

= [2b-7]/[b(b-3)]

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Cheers,
Stan H.