document.write( "Question 1039378: Identify the equation of the parabola with its focus at (-4,7) and the directrix y=1.
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Algebra.Com's Answer #654130 by Edwin McCravy(20065)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "The equation of a parabola is\r\n" );
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document.write( "4p(y-k) = (x-h)^2\r\n" );
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document.write( "Where \r\n" );
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document.write( "(h,k) is the vertex which is halfway between\r\n" );
document.write( "the directrix and the focus.\r\n" );
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document.write( "|p| is the distance from the focus to the vertex,\r\n" );
document.write( "and also from the vertex to the directrix. \r\n" );
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document.write( "p is taken as a positive number if the parabola opens\r\n" );
document.write( "upward, i.e., the directrix is below the vertex and focus.\r\n" );
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document.write( "p is taken as a negative number if the parabola opens\r\n" );
document.write( "downward, i.e., the directrix is above the vertex and focus.  \r\n" );
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document.write( "You can find those and substitute in\r\n" );
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document.write( "4p(y-k) = (x-h)^2\r\n" );
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document.write( "Edwin
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