document.write( "Question 409004: solve for x: log4 x- log4 (x+15)=-1 \n" ); document.write( "

Algebra.Com's Answer #288008 by nerdybill(7384) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"log%284%2Cx%29+-+log%284%2C%28x%2B15%29%29+=+-1\"$
\n" ); document.write( " $\"log%284%2Cx%2F%28x%2B15%29%29+=+-1\"$
\n" ); document.write( " $\"x%2F%28x%2B15%29+=+4%5E%28-1%29\"$
\n" ); document.write( " $\"x%2F%28x%2B15%29+=+1%2F4\"$
\n" ); document.write( "cross-multiplying:
\n" ); document.write( " $\"4x+=+x%2B15\"$
\n" ); document.write( " $\"3x+=+15\"$
\n" ); document.write( " $\"x+=+5\"$ \r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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