document.write( "Question 1035267: What is the equation of a parabola with the vertex (3,2) and focus (4,2)? \n" ); document.write( "
Algebra.Com's Answer #649925 by Edwin McCravy(20059)\"\" \"About 
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document.write( "The equation of a parabola is\r\n" );
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document.write( "(x-h)² = 4p(y-k) if the vertex and focus are above or below\r\n" );
document.write( "one another. p is positive if the vertex is below the focus\r\n" );
document.write( "and negative if the vertex is above the focus.\r\n" );
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document.write( "(y-k)² = 4p(x-h) if the vertex and focus are right or left\r\n" );
document.write( "of each other. p is positive if the vertex is left of the focus\r\n" );
document.write( "and negative if the vertex is to the right the focus. \r\n" );
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document.write( "where \r\n" );
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document.write( "h = the x-coordinate of the vertex = 3\r\n" );
document.write( "k = the y-coordinate of the vertex = 2\r\n" );
document.write( "p = the distance from the vertex to the focus.\r\n" );
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document.write( "The vertex (3,2) is left of the focus (4,2) so \r\n" );
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document.write( "The distance between the vertex (3,2) and focus (4,2)\r\n" );
document.write( "is 1 unit, and the vertex is left of the focus,\r\n" );
document.write( "so p = +1\r\n" );
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document.write( "Plug in the numbers for h, k, and p and leave x and y\r\n" );
document.write( "as letters, and you'll have the desired equation.\r\n" );
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document.write( "Here's the graph.  The blue line is the line of symmetry.\r\n" );
document.write( "It goes through both the vertex and the focus.\r\n" );
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document.write( "The green line is the directrix which is |p|\r\n" );
document.write( "units from the vertex, outside the parabola, and is\r\n" );
document.write( "perpendicular to the line of symmetry:\r\n" );
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document.write( "Edwin
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