document.write( "Question 26725: The sum of the digits is 9. If the digits are reversed, the new number is 45 more than the original number. Find the two digit number. \n" ); document.write( "

Algebra.Com's Answer #14541 by longjonsilver(2297) $\"\"$ $\"About$

You can put this solution on YOUR website!
we could probably do this by looking:\r
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\n" ); document.write( "\n" ); document.write( "Easy possibles are
\n" ); document.write( "18 and 81
\n" ); document.write( "27 and 72
\n" ); document.write( "36 and 63
\n" ); document.write( "45 and 54\r
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\n" ); document.write( "\n" ); document.write( "Looking, 27+45 is 72 so 27 is your answer.\r
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\n" ); document.write( "\n" ); document.write( "OK, mathematically...\r
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\n" ); document.write( "\n" ); document.write( "Let tens be x and units be y --> x+y = 9\r
\n" ); document.write( "\n" ); document.write( "Also, (10y+x) - (10x+y) = 45
\n" ); document.write( "10y+x-10x-y = 45
\n" ); document.write( "9y-9x = 45\r
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\n" ); document.write( "\n" ); document.write( "we have
\n" ); document.write( "y+x = 9
\n" ); document.write( "9y-9x = 45\r
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\n" ); document.write( "\n" ); document.write( "multiply first by 9 and we get
\n" ); document.write( "9y+9x = 81
\n" ); document.write( "9y-9x = 45\r
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\n" ); document.write( "\n" ); document.write( "Now subtract, leaving 18x = 36. So x = 2. Therefore, from x+y=9, y must be 7.\r
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\n" ); document.write( "\n" ); document.write( "jon.
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