document.write( "Question 867923: can a logarithm have 2 answers?
\n" ); document.write( "I have this equation that says solve for x:\r
\n" ); document.write( "\n" ); document.write( "Log base 4 of x + Log base 4 of (x+1) = Log base 4 of (x-1) + Log base 4 of 6\r
\n" ); document.write( "\n" ); document.write( "What I usually get is one negative solution which is false and one positive solution which is right, this time I got 2 positive answers... \r
\n" ); document.write( "\n" ); document.write( "x=2 & x=3\r
\n" ); document.write( "\n" ); document.write( "I know x=2 is the right one based on MathWay.com but how?! \n" ); document.write( "

Algebra.Com's Answer #523260 by mananth(16946) $\"\"$ $\"About$

You can put this solution on YOUR website!
A quadratic equation will always have two answers, unless it is a perfect square\r
\n" ); document.write( "\n" ); document.write( "if you simplify and remove the log since bases are same
\n" ); document.write( "we get
\n" ); document.write( "x(x+1)=6(x-1)\r
\n" ); document.write( "\n" ); document.write( "x^2+x=6x-6
\n" ); document.write( "x^2-5x+6=0\r
\n" ); document.write( "\n" ); document.write( "x^2-3x-2x+6=0\r
\n" ); document.write( "\n" ); document.write( "x(x-3)-2(x-3)=0\r
\n" ); document.write( "\n" ); document.write( "(x-2)(x-3)=0
\n" ); document.write( "so x=2 OR 3\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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