SOLUTION: Sorry if this isn't the right topic.... this is from an accuplacer practice test. I know the answer is 11z-20 over z(z-5) but don't understand how to work it. Here's the problem:

Algebra ->  Numeric Fractions Calculators, Lesson and Practice -> SOLUTION: Sorry if this isn't the right topic.... this is from an accuplacer practice test. I know the answer is 11z-20 over z(z-5) but don't understand how to work it. Here's the problem:      Log On


   

Question 302035: Sorry if this isn't the right topic.... this is from an accuplacer practice test. I know the answer is 11z-20 over z(z-5) but don't understand how to work it. Here's the problem: 4/z plus 7/z-5
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
4/z plus 7/z-5
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least common denominator: z(z-5)
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Rewrite each fraction with the lcd as its denominator:
(4(z-5))/lcd + (7z)/lcd
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Combine the numerators over the lcd:
[4z-20+7z)/lcd
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Simplify:
(11z-20)/[z(z-5)]
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Cheers,
Stan H.
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