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Jakevmi80
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Bunuel
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sashiim20
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OA:A

\(\frac{ab}{a-b}=1\)

\(ab=a-b\)

\(ab-a=-b\)

\(a(b-1)=-b\)

\(a= \frac{-b}{b-1}= \frac{b}{1-b}\)
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I just saw the condition b=/=1, and decided that I could just eliminate the options. Only one of the options has (1-b) in the denominator. Don't know if this approach is correct though haha.
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