document.write( "Question 134556: the additve inverse of a number divided by twelve is the same as one less than three times its reciprocal. \n" ); document.write( "
Algebra.Com's Answer #98438 by solver91311(24713)\"\" \"About 
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if \"a\" is the number, then the additive inverse is \"-a\" and its reciprocal is \"1%2Fa\". \"is the same as\" means \"equals\"\r
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\n" ); document.write( "\n" ); document.write( "The additive inverse of a number (\"-a\"), divided by 12 (\"-a%2F12\") is the same as (=) one less than (\"-1\") three times its reciprocal (\"3%2A%281%2Fa%29=3%2Fa\"). Put it all together:\r
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\n" ); document.write( "\n" ); document.write( "\"-a%2F12=%283%2Fa%29-1\"\r
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\n" ); document.write( "\n" ); document.write( "Add 1 to both sides:
\n" ); document.write( "\"1-a%2F12=3%2Fa\"\r
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\n" ); document.write( "\n" ); document.write( "LCD on the left is 12, so:
\n" ); document.write( "\"%2812-a%29%2F12=3%2Fa\"\r
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\n" ); document.write( "\n" ); document.write( "Cross-multiply (numerator on the left times denominator on the right equals denominator on the left times numerator on the right)
\n" ); document.write( "\"a%2812-a%29=36\"\r
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\n" ); document.write( "\n" ); document.write( "\"12a-a%5E2=36\"
\n" ); document.write( "\"-a%5E2%2B12a-36=0\"\r
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\n" ); document.write( "\n" ); document.write( "Multiply by -1:
\n" ); document.write( "\"a%5E2-12a%2B36=0\"\r
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\n" ); document.write( "\n" ); document.write( "Trinomial is a perfect square:
\n" ); document.write( "\"%28a-6%29%28a-6%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "Hence \"a=6\"\r
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\n" ); document.write( "\n" ); document.write( "Check:
\n" ); document.write( "\"-%286%29%2F12=%283%2F6%29-1\"
\n" ); document.write( "\"-1%2F2=1%2F2-1=-1%2F2\" Answer checks.
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