SOLUTION: If 2a/a + 1/a = 4, then a = ?

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Question 486663: If 2a/a + 1/a = 4, then a = ?
Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
You can get rid of the "a"s in the denominator by multiplying all terms on both sides by a as follows:
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%28a%2A2a%29%2Fa+%2B+%28a%2A1%29%2Fa+=+a%2A4
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The a in the numerator cancels with the a in the denominator as follows:
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%28cross%28a%29%2A2a%29%2Fcross%28a%29%2B+%28cross%28a%29%2A1%29%2Fcross%28a%29+=+4a
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and what's left is:
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2a+%2B+1+=+4a
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Subtract 4a from both sides:
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2a+-+4a+%2B+1+=+4a+-+4a
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and this simplifies to:
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-2a+%2B+1+=+0
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Next subtract 1 from both sides:
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-2a+%2B+1+-+1+=+-1
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On the left side the +1 and -1 cancel each other out and this reduces the equation to:
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-2a+=+-1
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Solve for a by dividing both sides by -2:
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%28-2a%29%2F%28-2%29+=+%28-1%29%2F%28-2%29
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and the answer becomes:
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a+=+1%2F2
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That's the answer to this problem.
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Hope this helps you to see your way through the problem.