document.write( "Question 149961: 2 log base 3 9x= 8 \n" ); document.write( "
Algebra.Com's Answer #110071 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"2%2Alog%283%2C%289x%29%29=8\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"log%283%2C%28%289x%29%5E2%29%29=8\" Rewrite the left side using the identity \"y%2Alog%28b%2C%28x%29%29=log%28b%2C%28x%5Ey%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"log%283%2C%2881x%5E2%29%29=8\" Square \"9x\" to get \"81x%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "\"3%5E8=81x%5E2\" Rewrite the equation using the property: \"log%28b%2C%28x%29%29=y\" ====> \"b%5Ey=x\"\r
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\n" ); document.write( "\n" ); document.write( "\"3%5E8=3%5E4x%5E2\" Rewrite \"81\" as \"3%5E4\"\r
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\n" ); document.write( "\n" ); document.write( "\"3%5E8%2F3%5E4=x%5E2\" Divide both sides by \"3%5E4\".\r
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\n" ); document.write( "\n" ); document.write( "\"3%5E%288-4%29=x%5E2\" Divide the terms on the left side by subtracting the exponents.\r
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\n" ); document.write( "\n" ); document.write( "\"3%5E%284%29=x%5E2\" Subtract\r
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\n" ); document.write( "\n" ); document.write( "\"81=x%5E2\" Raise 3 to the 4th power to get 81\r
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\n" ); document.write( "\n" ); document.write( "\"0%2B-sqrt%2881%29=x\" Take the square root of both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x=9\" or \"x=-9\" Take the square root of \"81\" to get \"9\" or \"-9\"\r
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\n" ); document.write( "\n" ); document.write( "Since you cannot take the log of negative number, this means that we must disregard the possible solution \"x=-9\"\r
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\n" ); document.write( "\n" ); document.write( "So the only solution is \"x=9\"
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