SOLUTION: I need help with this problem. a-3/a+7÷a^2-9/a^2+4a-21

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Question 453106: I need help with this problem.
a-3/a+7÷a^2-9/a^2+4a-21
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
a-3/a+7÷a^2-9/a^2+4a-21
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[(a-3)/(a+7)] / [(a-3)(a+3)/(a+7)(a-3)]
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Invert and multiply:
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[(a-3)/(a+7)] / [(a+7)(a-3)/(a-3)(a+3)]
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Cancel factors common to a numerator and a denominator:
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[(a-3)/1] * [1/(a+3)]
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= (a-3)/(a+3)
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Cheers,
Stan H.
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