SOLUTION: A two-digit number exceeds twice the sum of its digits by 7. Find the number if its tens digits is smaller than its units digit also by 7. Thanks for solving.

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Question 717182: A two-digit number exceeds twice the sum of its digits by 7. Find the number if its tens digits is smaller than its units digit also by 7.
Thanks for solving.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A two-digit number exceeds twice the sum of its digits by 7. Find the number if its tens digits is smaller than its units digit also by 7.
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Equations:
10t+u = 2(t+u)+7
t = u - 7
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Rearrange:
8t - u = 7
t - u = -7
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Subtract and solve for "t":
7t = 14
t = 2
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Solve for "u" using t-u = -7
2 - u = -7
u = 9
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Ans: The number is 10t+u = 29
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Cheers,
Stan H.
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