document.write( "Question 560460: solve for x:\r
\n" ); document.write( "\n" ); document.write( "log base 3 (7x+4)-log base 3 of 2 = 2logbase3 of X
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Algebra.Com's Answer #363886 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
\"+log%283%2C+%287x+%2B+4%29%29+-+log%283%2C2%29+=+2%2Alog%283%2Cx%29+\"
\n" ); document.write( "Use the rule
\n" ); document.write( "\"+log%28a%29+-+log%28b%29+=+log%28a%2Fb%29+\"
\n" ); document.write( "\"+log%283%2C++%28%287%2F2%29%2Ax+%2B+2%29+%29+=+2%2Alog%283%2Cx%29+\"
\n" ); document.write( "Use the rule
\n" ); document.write( "\"+a%2Alog%28b%29+=+log%28b%5Ea%29+\"
\n" ); document.write( "\"+log%283%2C+%28%287%2F2%29%2Ax+%2B+2%29+%29+=+log%283%2Cx%5E2%29+\"
\n" ); document.write( "\"+%287%2F2%29%2Ax+%2B+2+=+x%5E2+\"
\n" ); document.write( "\"+x%5E2+-+%287%2F2%29%2Ax+-+2+=+0+\"
\n" ); document.write( "\"+2x%5E2+-+7x+-+4+=+0+\"
\n" ); document.write( "Use the 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+=+2+\"
\n" ); document.write( "\"+b+=+-7+\"
\n" ); document.write( "\"+c+=+-4+\"
\n" ); document.write( "\"+x+=+%28-%28-7%29+%2B-+sqrt%28+%28-7%29%5E2-4%2A2%2A%28-4%29+%29%29%2F%282%2A2%29+\"
\n" ); document.write( "\"+x+=+%28+7+%2B-+sqrt%28+49+%2B+32+%29%29+%2F+4+\"
\n" ); document.write( "\"+x+=+%28+7+%2B-+sqrt%28+81+%29%29+%2F+4+\"
\n" ); document.write( "\"+x+=+%28+7+%2B+9+%29%2F4+\"
\n" ); document.write( "\"+x+=+4+\"
\n" ); document.write( "and, taking the (-) square root,
\n" ); document.write( "\"+x+=+%28+7+-+9+%29+%2F+4+\"
\n" ); document.write( "\"+x+=+-2%2F4+\"
\n" ); document.write( "\"+x+=+-%281%2F2%29+\"
\n" ); document.write( "--------------
\n" ); document.write( "Using \"+x+=+4+\",
\n" ); document.write( "\"+log%283%2C+%287x+%2B+4%29%29+-+log%283%2C2%29+=+2%2Alog%283%2Cx%29+\"
\n" ); document.write( "\"+log%283%2C+%287%2A4+%2B+4%29%29+-+log%283%2C2%29+=+2%2Alog%283%2C4%29+\"
\n" ); document.write( "\"+log%283%2C+32%29+b-+log%283%2C+2%29+=+2%2Alog%283%2C4%29+\"
\n" ); document.write( "\"+log%283%2C+%2832%2F2%29%29+=+log%283%2C4%5E2%29+\"
\n" ); document.write( "\"+log%283%2C16%29+=+log%283%2C16%29+\"
\n" ); document.write( "OK
\n" ); document.write( "Using \"+x+=+-%281%2F2%29+\"
\n" ); document.write( "
\n" ); document.write( "I have to reject this solution for \"x\" because of the
\n" ); document.write( "right side. It is impossible to raise the base \"3\" to
\n" ); document.write( "some power ( + or - ) that will result in \"+-%281%2F2%29+\",
\n" ); document.write( "or any negative number.
\n" ); document.write( "So, \"+x+=+4+\" is the only solution
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