document.write( "Question 387058: ln(x-5)+ln(x+1)=ln40 \n" ); document.write( "

Algebra.Com's Answer #273573 by Fombitz(32388) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"ln%28x-5%29%2Bln%28x%2B1%29=ln%2840%29\"$
\n" ); document.write( " $\"ln%28%28x-5%29%28x%2B1%29%29=ln%2840%29\"$
\n" ); document.write( " $\"%28x-5%29%28x%2B1%29=40\"$
\n" ); document.write( " $\"x%5E2-4x-5=40\"$
\n" ); document.write( " $\"x%5E2-4x-45=0\"$
\n" ); document.write( " $\"%28x-9%29%28x%2B5%29=0\"$
\n" ); document.write( "Two solutions:
\n" ); document.write( " $\"x-9=0\"$
\n" ); document.write( " $\"highlight%28x=9%29\"$
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( " $\"x%2B5=0\"$
\n" ); document.write( " $\"x=-5\"$
\n" ); document.write( "However, the ln function requires positive arguments so this solution is not valid.
\n" ); document.write( " \n" ); document.write( "

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