document.write( "Question 447944: solve for u\r
\n" ); document.write( "\n" ); document.write( "log3 (u + 18) + log3 (u) = 5 \n" ); document.write( "

Algebra.Com's Answer #308298 by Alan3354(69443) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"log%283%2C%28u+%2B+18%29%29+%2B+log%283%2C%28u%29%29+=+5\"$
\n" ); document.write( " $\"log%283%2C%28u%28u+%2B+18%29%29%29+=+5\"$
\n" ); document.write( " $\"u%28u+%2B+18%29+=+3%5E5+=+243\"$
\n" ); document.write( " $\"u%5E2+%2B+18u+-+243+=+0\"$
\n" ); document.write( "(u+27)(u-9) = 0
\n" ); document.write( "-27 gives log of neg #s, reject
\n" ); document.write( "u = 9
\n" ); document.write( " \n" ); document.write( "

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