Question 171120: the sum of the digits of a two-digit number is 13. twice the first digit is 1 less than the second digit. what is the two-digit number? Answer by Mathtut(3670) (Show Source):
You can put this solution on YOUR website! lets call the tens digit a and the ones digit b
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a+b= 13...eq 1
2a=b-1....eq 2
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lets re write eq 1 to a=13-b and take that value and plug it into eq 2
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2(13-b)=b-1
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26-2b=b-1
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3b=27
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number is
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