document.write( "Question 1096584: the sum of two digit number and the number obtained by interchanging its digits is 99. find the number \n" ); document.write( "

Algebra.Com's Answer #711013 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "Let  a  and  b be the digits of your number  n,  so that  n = 10a + b.\r\n" );
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document.write( "The number after reversing digits is  10b + a.\r\n" );
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document.write( "Then from the condition you have the system of two equations for the unknowns  a  and  b:\r\n" );
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document.write( "Now,  simplify it:\r\n" );
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document.write( "Simplify it one more time:\r\n" );
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document.write( ". \r\n" );
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document.write( "So, you have, actually, only ONE equation for the digits and do not have any additional info.\r\n" );
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document.write( "Therefore, the answer is not unique.\r\n" );
document.write( "All the numbers  18,  27,  36,  45,  54,  63,  72,  81  are the solutions.\r\n" );
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\n" ); document.write( "On problems for digits reversing see the lesson\r
\n" ); document.write( "\n" ); document.write( " - Word problems on reversing digits of numbers\r
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