document.write( "Question 203804: How do I solve log(2x + 1) – log(x + 4) =0 ? \n" ); document.write( "

Algebra.Com's Answer #153786 by Earlsdon(6294) $\"\"$ $\"About$

You can put this solution on YOUR website!
Solve for x:
\n" ); document.write( " $\"log%28%282x%2B1%29%29-log%28%28x%2B4%29%29+=+0\"$ Apply the quotient rule for logarithms: $\"log%28%28M%29%29-log%28%28N%29%29+=+log%28%28M%2FN%29%29\"$
\n" ); document.write( " $\"log%28%28%282x%2B1%29%29%2F%28%28x%2B4%29%29%29+=+0\"$ Express this in exponential form: $\"Log%5Bb%5D%28x%29+=+y\"$ means $\"b%5Ey+=+x\"$
\n" ); document.write( " $\"10%5E0+=+%28%282x%2B1%29%2F%28x%2B4%29%29\"$ Substitute $\"10%5E0+=+1\"$
\n" ); document.write( " $\"1+=+%28%282x%2B1%29%2F%28x%2B4%29%29\"$ Multiply both sides by (x+4)
\n" ); document.write( " $\"x%2B4+=+2x%2B1\"$ Subtract x from both sides.
\n" ); document.write( " $\"4+=+x%2B1\"$ Subtract 1 from both sides.
\n" ); document.write( " $\"3+=+x\"$ or $\"highlight%28x+=+3%29\"$ \n" ); document.write( "

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