SOLUTION: how do i solve 5 over 2x-12 - 20 over x squared-4x-12?

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Question 440425: how do i solve 5 over 2x-12 - 20 over x squared-4x-12?
Found 2 solutions by stanbon, lwsshak3:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
how do i solve 5 over 2x-12 - 20 over x squared-4x-12?
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5/(2x-12) - 20/(x^2-4x-12)
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Factor:
5/(2(x-6)) - 20/[(x-6)(x+2)]
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lcd: 2(x+2)(x-6)
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Rewrite each fraction with the lcd as its denominator:
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[5(x+2)]/lcd - [20(2)]/lcd
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Combine the numerators over the lcd:
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[5x+10-40]/lcd
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[5x-30]/lcd
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[5(x-6)]/[2(x+2)(x-6)]
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Cancel x-6
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= 5/[2(x+2)]
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Cheers,
Stan H.

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
how do i solve 5 over 2x-12 - 20 over x squared-4x-12?
..
5/(2x-12)-20/(x^2-4x-12)
5/2(x-6)-20(x-6)(x+2)
LCD=2(x-6)(x+2)
multiply both terms by the LCD and divide the result by the LCD
(5(x+2)-20*2)/2(x-6)(x+2)
(5x+10-40)/2(x-6)(x+2)
5x-30/2(x-6)(x+2)
5(x-6)/2(x-6)(x+2)
cancel out (x-6)
5/2(x+2) (ans)