document.write( "Question 272864: 27^x =9^-x-1 \n" ); document.write( "
Algebra.Com's Answer #199425 by Alan3354(69443)\"\" \"About 
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27^x =9^-x-1
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\n" ); document.write( "There's more than 1 approach to this.
\n" ); document.write( "The simplest is:
\n" ); document.write( "Both 27 and 9 are integral powers of 3, so change to base 3.
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\n" ); document.write( "27^x =9^-x-1
\n" ); document.write( "3^3x = 3^(-2x-2)
\n" ); document.write( "3x = -2x-2
\n" ); document.write( "5x = -2
\n" ); document.write( "x = -0.4
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\n" ); document.write( "Or,
\n" ); document.write( "x*log(27) = (-x-1)*log(9) = x(-log(9)) - log(9)
\n" ); document.write( "xlog(27) + xlog(9) = -log(9)
\n" ); document.write( "x(log(27) + log(9)) = -log(9)
\n" ); document.write( "x*log(243) = -log(9)
\n" ); document.write( "x = -log(9)/log(243)
\n" ); document.write( "x = -0.4\r
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