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document.write( "The solution using the quadratic formula:\r\n" );
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document.write( "
\r\n" );
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document.write( "simplifies to\r\n" );
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\r\n" );
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document.write( "We only need to require that the larger\r\n" );
document.write( "solution, the one with the plus sign before\r\n" );
document.write( "the square root, be negative, so\r\n" );
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document.write( "
\r\n" );
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document.write( "The discriminant must be positive to prevent\r\n" );
document.write( "getting 1 single or 2 imaginary solutions, so \r\n" );
document.write( "setting the discriminant greater than 0,\r\n" );
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document.write( "
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document.write( "That has solutions k < -4 or k > 4.\r\n" );
document.write( "If k > 4 then certainly the larger solution \r\n" );
document.write( "will be positive.\r\n" );
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document.write( "So we must take k < -4\r\n" );
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document.write( "Multiplying both sides by 2\r\n" );
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document.write( "
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document.write( "
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document.write( "
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document.write( "
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document.write( "Therefore to have both solutions negative,\r\n" );
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document.write( "
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document.write( "Edwin
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document.write( "![\"\"](\"/images/stars/stars-13.gif\")
