SOLUTION: 10+20radical6 (I have no radical symbol) / ( divided by) radical 6 -2 Rationalize the demonstrator and simplify the expression. What is the value of b if the answer is expre

Algebra ->  Radicals -> SOLUTION: 10+20radical6 (I have no radical symbol) / ( divided by) radical 6 -2 Rationalize the demonstrator and simplify the expression. What is the value of b if the answer is expre      Log On


   

Question 1033562: 10+20radical6 (I have no radical symbol) / ( divided by) radical 6 -2

Rationalize the demonstrator and simplify the expression. What is the value of b if the answer is expressed in the format a + b radical 6?
I think I am messinibg up the equation somehow. The answers I have are not plugging back in. 2, 5, 10 and 15.
I am confused about the solution.
Thanks.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
10+20radical6 (I have no radical symbol) / ( divided by) radical 6 -2
Rationalize the demonstrator and simplify the expression. What is the value of b if the answer is expressed in the format a + b radical 6?1
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(10 + 20*sqrt(6))/(-2+sqrt(6))
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(10)(1 + 2sqrt(6))/(-2 + sqrt(6))
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Multiply numerator and denominator by (-2-sqrt(6)) to get:
10[(1+2sqrt(6))(-2-sqrt(6))] / [(-2+sqrt(6))(-2-sqrt(6))]
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= 10[-2-2*6-5sqrt(6)] / [4-6]
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= 10[-14 - 5sqrt(6)]/(-2)
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= -5[-14 - 5sqrt(6)]
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= 70 + 25sqrt(6)
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b = 25
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Cheers,
Stan H.
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