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Old 10-22-2006   #1
Sillysidley

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Unhappy I'm stuck

Find 2x+5 if x satisfies sqrt(40-9x)-2sqrt(7-x)=sqrt(-x)

I'm stuck HElP!!!
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Old 10-22-2006   #2
Mr. Hui


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First, square both sides to remove complex (imaginary) numbers.

Then, solve equation for x. It involves manipulating radicals.
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Last edited by Mr. Hui; 10-22-2006 at 01:48 PM..
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Old 10-22-2006   #3
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Radicals are expression involving the square root symbol.
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Old 10-25-2006   #4
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Default I don't know about this...

Is x=1??????

Thanks for the help
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Old 10-25-2006   #5
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Default sorry/is the answer to the problem 7

Whoops, didn't read the question.

Is the answer to the problem 7?
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Old 10-25-2006   #6
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No, if you plug in x = 7, you won't get the two sides equal. I will provide you with a complete solution.
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Old 10-25-2006   #7
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I made a mistake

it should be something like 40-9x+7+x+2sqrt...
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Old 10-26-2006   #8
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As promised, here is the completely worked out solution.

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Old 10-26-2006   #9
Alex a.k.a whiteboy
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Default wtf

wtf dont show that again
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Old 10-30-2006   #10
puppydog
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show what??
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