document.write( "Question 1183047: 8^x-2 = 2/25, find x \n" ); document.write( "
Algebra.Com's Answer #813197 by ikleyn(52781)\"\" \"About 
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\n" ); document.write( "8^x-2 = 2/25, find x
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document.write( "Your starting equation is\r\n" );
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document.write( "    \"8%5E%28x-2%29\" = \"2%2F25\".\r\n" );
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document.write( "It is equivalent to\r\n" );
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document.write( "    \"2%5E%283%2A%28x-2%29%29\" = \"8%2F100\".\r\n" );
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document.write( "Take logarithm base 10 of both sides\r\n" );
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document.write( "    3*(x-2)*log(2) = 3*log(2) - 2\r\n" );
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document.write( "Simplify\r\n" );
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document.write( "    (3x - 6)*log(2) = 3*log(2) - 2\r\n" );
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document.write( "    (3x - 6 - 3)*log(2) = -2\r\n" );
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document.write( "    (3x - 9)*log(2) = -2\r\n" );
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document.write( "     3x - 9 = - \"2%2Flog%28%282%29%29\"\r\n" );
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document.write( "     3x     = - \"2%2Flog%28%282%29%29\" + 9\r\n" );
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document.write( "      x     = - \"2%2F%283%2Alog%28%282%29%29%29\" + 3 = 0.785381  (approximately; rounded).    ANSWER\r\n" );
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document.write( "CHECK.  The left side of the original equation is  \"8%5E%280.785381-2%29\" = 0.080000 = \"8%2F100\" = \"2%2F25\".    ! Correct !\r\n" );
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