\r\n" );
document.write( "what is the equation of the line of symmetry for y = -x² + 4x + 5\r\n" );
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document.write( "The vertex for the quadratic equation:\r\n" );
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document.write( "y = ax² + bx + c\r\n" );
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document.write( "is given by the formula:\r\n" );
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document.write( "(
, 
), where D = discriminant = 
\r\n" );
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document.write( "and the line of symmetry is the vertical line\r\n" );
document.write( "whose equation is \r\n" );
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document.write( "x = \r\n" );
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document.write( "==============================\r\n" );
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document.write( "For the quadratic equation:\r\n" );
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document.write( "y = -x² + 4x + 5\r\n" );
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document.write( "a = -1, b = 4, c = 5\r\n" );
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document.write( "D = discriminant = = 
= 
= 
\r\n" );
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document.write( "So the vertex is\r\n" );
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document.write( "(, ) = (
, 
) = \r\n" );
document.write( "(
, 
) = (
, 
), \r\n" );
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document.write( "and the line of symmetry is the vertical line\r\n" );
document.write( "whose equation is \r\n" );
document.write( "\r\n" );
document.write( "x = \r\n" );
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document.write( "or\r\n" );
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document.write( "x = 2\r\n" );
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document.write( "Here is the graph of the quadratic and the\r\n" );
document.write( "green vertical line is the line of symmetry,\r\n" );
document.write( "notice it crosses the x axis at 2.\r\n" );
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document.write( "
\r\n" );
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document.write( "Edwin
\n" );
document.write( "![\"\"](\"/images/stars/stars-13.gif\")
