document.write( "Question 647180: I am thinking of a 2 digit number. The sum of the digits is 8. If I reverse the 2 digits then the value of the new number is 18 more than the orginal number. What is the orginal number?\r
\n" ); document.write( "\n" ); document.write( "-Do not understand, please help. \n" ); document.write( "
Algebra.Com's Answer #406021 by stanbon(75887)\"\" \"About 
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I am thinking of a 2 digit number. The sum of the digits is 8. If I reverse the 2 digits then the value of the new number is 18 more than the orginal number. What is the orginal number?
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\n" ); document.write( "Let the number be 10t+u (t is the tens digit; u is the units digit)
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\n" ); document.write( "Equation:
\n" ); document.write( "t + u = 8
\n" ); document.write( "10u+t = 10t+u + 18
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\n" ); document.write( "Substitute for \"t\" and solve for \"u\":
\n" ); document.write( "10u + (8-u) = 10(8-u)+u + 18
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\n" ); document.write( "10u - 9(8-u) = u+18
\n" ); document.write( "10u -72+9u = u+18
\n" ); document.write( "18u = 90
\n" ); document.write( "u = 5 (that is the units digit)
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\n" ); document.write( "Solve for \"t\":
\n" ); document.write( "t = 8-u
\n" ); document.write( "t = 8-5
\n" ); document.write( "t = 3
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\n" ); document.write( "Original Number: 10t+u = 35
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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