document.write( "Question 147610: ln(x+3)+ln4=ln40 \n" ); document.write( "
Algebra.Com's Answer #107978 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"ln%28x%2B3%29%2Bln%284%29=ln%2840%29\" Start with the given equation.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"ln%28%28x%2B3%29%284%29%29=ln%2840%29\" Combine the logs using the identity \"ln%28A%29%2Bln%28B%29=ln%28A%2AB%29\".\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"ln%284x%2B12%29=ln%2840%29\" Distribute.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"4x%2B12=40\" Since the logs are equal with the same base, this means that the arguments are equal.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"4x=40-12\" Subtract \"12\" from both sides.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"4x=28\" Combine like terms on the right side.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"x=%2828%29%2F%284%29\" Divide both sides by \"4\" to isolate \"x\".\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"x=7\" Reduce.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "----------------------------------------------------------------------\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Answer:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "So the answer is \"x=7\" \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" );