You can put this solution on YOUR website! 3\13 + [-4\7]
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least common denominator: 13*7
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Rewrite each fraction with the lcd as its denominator:
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[3*7/lcd] + (-4*13/lcd]
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Combine the numerators over the lcd:
[21 - 52]/lcd
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= -31/91
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Cheers,
Stan H.
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