document.write( "Question 493969: The units digit of a two-digit number is twice of the tens digit. Find the two digit number, If the value are interchanged, it is equal to 9 more than the original number.\r
\n" ); document.write( "\n" ); document.write( "Please help me what's the answer \n" ); document.write( "
Algebra.Com's Answer #335507 by stanbon(75887)\"\" \"About 
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The units digit of a two-digit number is twice of the tens digit. Find the two digit number, If the value are interchanged, it is equal to 9 more than the original number.
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\n" ); document.write( "Let the number be 10t + u
\n" ); document.write( "where t is the ten's digit and u is the unit's digit.
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\n" ); document.write( "Equation:
\n" ); document.write( "u = 2t
\n" ); document.write( "10u+t = 10t+u+9
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\n" ); document.write( "9u -9t = 9
\n" ); document.write( "Divide thru by 9 to get:
\n" ); document.write( "u - t = 1
\n" ); document.write( "Substitute for \"u\" and solve for \"t\":
\n" ); document.write( "2t-t = 1
\n" ); document.write( "t = 1
\n" ); document.write( "----
\n" ); document.write( "solve for \"u\"
\n" ); document.write( "u = 2t
\n" ); document.write( "u = 2
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\n" ); document.write( "The original number is 12
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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