SOLUTION: Please Help me to answer this... The tens digit of a 2-digit number is 3 more than the ones digit. the number is equal to 7 times the sum of the digits. find the number.

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Question 778258: Please Help me to answer this...
The tens digit of a 2-digit number is 3 more than the ones digit. the number is equal to 7 times the sum of the digits. find the number.
Answer by MathTherapy(10552) About Me  (Show Source):
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Please Help me to answer this...
The tens digit of a 2-digit number is 3 more than the ones digit. the number is equal to 7 times the sum of the digits. find the number.

Let the tens and units digits be T and U, respectively
Then: T = U + 3 ----- eq (i)

10T + U = 7(T + U) ------ 10T + U = 7T + 7U ------ 10T – 7T + U – 7U = 0 ---- 3T – 6U = 0 ---- 3(T – 2U) = 3(0)
T – 2U = 0 ------ eq (ii)
U + 3 – 2U = 0 --------- Substituting U + 3 for T in eq (ii)
U – 2U = - 3
- U = - 3

U, or units digit = %28-+3%29%2F-+1, or 3

T – 2(3) = 0 ---- Substituting 3 for U in eq (ii)
T – 6 = 0

T, or tens digit = 6

Number is: highlight_green%2863%29

You can do the check!!

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