document.write( "Question 502890: A two digit number is 3 times the sum of it's digits. The number is also 45 less than the number formed by reversing the digits and the original number. What is the original number? \n" ); document.write( "
Algebra.Com's Answer #338995 by ankor@dixie-net.com(22740)\"\" \"About 
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Let x = the 10's digit, let y = the units
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\n" ); document.write( "A two digit number is 3 times the sum of it's digits.
\n" ); document.write( "10x + y = 3(x+y)
\n" ); document.write( "10x + y = 3x + 3y
\n" ); document.write( "10x - 3x = 3y - y
\n" ); document.write( "7x = 2y
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\n" ); document.write( "The number is also 45 less than the number formed by reversing the digits and the original number.
\n" ); document.write( "10x + y = 10y - x - 45
\n" ); document.write( "10x - x = 10y - y - 45
\n" ); document.write( "9x = 9y - 45
\n" ); document.write( "simplify, divide by 9
\n" ); document.write( "x = y - 5
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\n" ); document.write( "In the 1st simplified equation replace x with (y-5)
\n" ); document.write( "7(y-5) = 2y
\n" ); document.write( "7y - 35 = 2y
\n" ); document.write( "7y - 2y = 35
\n" ); document.write( "5y = 35
\n" ); document.write( "y = 35/5
\n" ); document.write( "y = 7 is the units digit (original number)
\n" ); document.write( "and
\n" ); document.write( "x = 7 - 5
\n" ); document.write( "x = 2 is the 10's digit
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\n" ); document.write( "27 is the number
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\n" ); document.write( "Check it in the statement:
\n" ); document.write( "\"A two digit number is 3 times the sum of it's digits.
\n" ); document.write( "27 = 3(7+2) \n" ); document.write( "
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