document.write( "Question 271141: The sum of the digits of a certain 2-digit number is 13. When you reverse the number, the new number is 9 less than the original number. The difference between the 2 digits is 1. Find the original number. \n" ); document.write( "
Algebra.Com's Answer #198685 by ankor@dixie-net.com(22740)\"\" \"About 
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The two digit number: 10x + y
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\n" ); document.write( "The sum of the digits of a certain 2-digit number is 13.
\n" ); document.write( "x + y = 13
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\n" ); document.write( " When you reverse the number, the new number is 9 less than the original number.
\n" ); document.write( "10y + x = 10x + y - 9
\n" ); document.write( "10y - y = 10x - x - 9
\n" ); document.write( "9y = 9x - 9
\n" ); document.write( "simplify, divide by 9
\n" ); document.write( "y = x - 1\r
\n" ); document.write( "\n" ); document.write( " Find the original number.
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\n" ); document.write( "replace y in the 1st equation with (x-1)
\n" ); document.write( "x + (x-1) = 13
\n" ); document.write( "2x = 13 + 1
\n" ); document.write( "2x = 14
\n" ); document.write( "x = 7
\n" ); document.write( "then
\n" ); document.write( "y = 6
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\n" ); document.write( "76 is the number
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\n" ); document.write( "Check solution in the statement:
\n" ); document.write( "\"When you reverse the number, the new number is 9 less than the original\"
\n" ); document.write( "67 = 76 - 9 \n" ); document.write( "
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