SOLUTION: The sum of the digit of a two digit number is 9. the number is 6 times the units digit. find the number

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Question 1046710: The sum of the digit of a two digit number is 9. the number is 6 times the units digit. find the number
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +t+ = the tens digit
Let +u+ = the units digit
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(1) +t+%2B+u+=+9+
(2) +10t+%2B+u+=+6u+
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(2) +10t+=+5u+
(2) +2t+=+u+
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Substitute (2) into (1)
(1) +t+%2B+2t+=+9+
(1) +3t+=+9+
(1) +t+=+3+
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(2) +u+=+2t+
(2) +u+=+2%2A3+
(2) +u+=+6+
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The number is 36
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check:
(2) +10t+%2B+u+=+6u+
(2) +10%2A3+%2B+6+=+6%2A6+
(2) +30+%2B+6+=+36+
(2) +36+=+36+
OK