document.write( "Question 281573: how do you solve
\n" ); document.write( "ln (2x+3)+ln(x-6)-2 ln x =0
\n" ); document.write( "Thank you soooo much
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Algebra.Com's Answer #204548 by nerdybill(7384)\"\" \"About 
You can put this solution on YOUR website!
Applying \"log rules\":
\n" ); document.write( "ln (2x+3)+ln(x-6)-2 ln x =0
\n" ); document.write( "ln (2x+3)+ln(x-6)- ln x^2 =0
\n" ); document.write( "ln (2x+3)(x-6)- ln x^2 =0
\n" ); document.write( "ln [(2x+3)(x-6)]/x^2 =0
\n" ); document.write( "[(2x+3)(x-6)]/x^2 = e^0
\n" ); document.write( "[(2x+3)(x-6)]/x^2 = 1
\n" ); document.write( "(2x+3)(x-6) = x^2
\n" ); document.write( "2x^2-12x+3x-18 = x^2
\n" ); document.write( "2x^2-9x-18 = x^2
\n" ); document.write( "x^2-9x-18 = 0
\n" ); document.write( "Solve by applying the quadratic equation. This results in:
\n" ); document.write( "x = {10.685, -1.685}
\n" ); document.write( "But, we can toss out the negative solution since this results in taking a ln of a negative number. This is an extraneous solution -- toss it out. Leaving our solution as:
\n" ); document.write( "x = 10.685
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\n" ); document.write( "Details of quadratic equation follows:
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"1x%5E2%2B-9x%2B-18+=+0\") has the following solutons:
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\n" ); document.write( " \"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
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\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
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\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%28-9%29%5E2-4%2A1%2A-18=153\".
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\n" ); document.write( " Discriminant d=153 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--9%2B-sqrt%28+153+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-9%29%2Bsqrt%28+153+%29%29%2F2%5C1+=+10.6846584384265\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-9%29-sqrt%28+153+%29%29%2F2%5C1+=+-1.68465843842649\"
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\n" ); document.write( " Quadratic expression \"1x%5E2%2B-9x%2B-18\" can be factored:
\n" ); document.write( " \"1x%5E2%2B-9x%2B-18+=+1%28x-10.6846584384265%29%2A%28x--1.68465843842649%29\"
\n" ); document.write( " Again, the answer is: 10.6846584384265, -1.68465843842649.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B-9%2Ax%2B-18+%29\"

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