document.write( "Question 663329: log(9x+5)-log(x^(2)-1)=1/2 \n" ); document.write( "

Algebra.Com's Answer #412864 by lwsshak3(11628) $\"\"$ $\"About$

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log(9x+5)-log(x^(2)-1)=1/2
\n" ); document.write( "place under single log
\n" ); document.write( "log[(9x+5)/(x^2-1)]=1/2
\n" ); document.write( "convert to exponential form:
\n" ); document.write( "10^(1/2)=(9x+5)/(x^2-1)=√10
\n" ); document.write( "√10(x^2-1)=9x+5
\n" ); document.write( "√10x^2-√10=9x+5
\n" ); document.write( "√10x^2-9x-√10-5=0
\n" ); document.write( "3.16x^2-9x-8.16=0
\n" ); document.write( "solve by following 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=3.16, b=-9, c=-8.16
\n" ); document.write( "ans:
\n" ); document.write( "x≈-0.723(reject, (9x+5)>0)
\n" ); document.write( "or
\n" ); document.write( "x≈3.571 \n" ); document.write( "

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