SOLUTION: For a particular two digit number, the value of the number is 9 more than when the digits are reversed. In fact, if you add 4 to the first digit it is the same as doubling the se

Algebra ->  Expressions-with-variables -> SOLUTION: For a particular two digit number, the value of the number is 9 more than when the digits are reversed. In fact, if you add 4 to the first digit it is the same as doubling the se      Log On


   

Question 1007658: For a particular two digit number, the value of the number is 9 more than when the digits are reversed. In fact, if you add 4 to the first digit it is the same as doubling the second digit.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
For a particular two digit number, the value of the number is 9 more than when the digits are reversed. In fact, if you add 4 to the first digit it is the same as doubling the second digit.
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Let the number be 10t+u
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Equations:
10t+u = 10u+t + 9
t+4 = 2u
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Substitute for "t" and solve for "u"::
10(2u-4) + u = 10u+2u-4 + 9
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21u - 40 = 12u + 5
9u = 45
u = 5
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t = 2u-4 = 6
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Ans: number = 65
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Cheers,
Stan H.
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