document.write( "Question 810322: How do you solve this?\r
\n" ); document.write( "\n" ); document.write( "log(x+4)+log(x)=9 \n" ); document.write( "

Algebra.Com's Answer #488060 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"+log%28+x%2B4+%29+%2B+log%28+x+%29+=+9+\"$
\n" ); document.write( "Make the substitution:
\n" ); document.write( " $\"+9+=+log%28+10%5E9+%29+\"$
\n" ); document.write( " $\"+log%28+x%2B4+%29+%2B+log%28+x+%29+=+log%28+10%5E9+%29+\"$
\n" ); document.write( " $\"+log%28+%28x%2B4%29%2Ax+%29+=+log%28+10%5E9+%29+\"$
\n" ); document.write( " $\"+%28+x%2B4+%29%2Ax+=+10%5E9+\"$
\n" ); document.write( " $\"+x%5E2+%2B+4x+-+10%5E9+\"$
\n" ); document.write( "Use quadratic formula
\n" ); document.write( " $\"+x+=+%28-b+%2B-+sqrt%28+b%5E2+-+4%2Aa%2Ac+%29%29+%2F+%282%2Aa%29+\"$
\n" ); document.write( " $\"+a+=+1+\"$
\n" ); document.write( " $\"+b+=+4+\"$
\n" ); document.write( " $\"+c+=+-10%5E9+\"$
\n" ); document.write( " $\"+x+=+%28-4+%2B-+sqrt%28+4%5E2+-+4%2A1%2A%28-10%5E9+%29%29%29+%2F+%282%2A1%29+\"$
\n" ); document.write( " $\"+x+=+%28-4+%2B-+sqrt%28+16+%2B+4000000000+%29%29+%2F+2+\"$
\n" ); document.write( "The answer looks pretty strange. I
\n" ); document.write( "think my method is OK, but the results
\n" ); document.write( "are a little odd
\n" ); document.write( "I would get another opinion\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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