document.write( "Question 1138529: Log2(x^2-9)=4 \n" ); document.write( "

Algebra.Com's Answer #756319 by ikleyn(52803) $\"\"$ $\"About$

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document.write( " = \r\n" );
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document.write( "is equivalent to\r\n" );
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document.write( "     =     (by the definition of the logarithm)\r\n" );
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document.write( "which, in turn, is equivalent to\r\n" );
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document.write( "     = ,   or\r\n" );
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document.write( "     = 25.\r\n" );
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document.write( "Hence,  x =  = +/- 5.\r\n" );
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document.write( "ANSWER.  The given equation has two solutions,  x= 5  and  x= -5.\r\n" );
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