document.write( "Question 1135976: Find the vertex, focus, directrix, and focal width of the parabola.
\n" ); document.write( "x2 = 20y
\n" ); document.write( "choices are below\r
\n" ); document.write( "\n" ); document.write( "Vertex: (0, 0); Focus: (0, 5); Directrix: y = -5; Focal width: 20
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\n" ); document.write( "Vertex: (0, 0); Focus: (5, 0); Directrix: x = 5; Focal width: 5
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\n" ); document.write( "Vertex: (0, 0); Focus: (5, 0); Directrix: y = 5; Focal width: 80
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\n" ); document.write( "Vertex: (0, 0); Focus: (0, -5); Directrix: x = -5; Focal width: 80
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Algebra.Com's Answer #753735 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "\"x%5E2+=+20y+\"\r
\n" ); document.write( "\n" ); document.write( "\"4p%28y-k%29=%28x-h%29%5E2\" is the standard equation for a right-left facing parabola with vertex at (\"h\", \"k\" )\r
\n" ); document.write( "\n" ); document.write( "rewrite \"x%5E2+=+20y+\" in the standard form :\r
\n" ); document.write( "\n" ); document.write( "\"20y=x%5E2\".........factor \"4\"\r
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\n" ); document.write( "\n" ); document.write( "\"4%2820%29%2F4%29y=x%5E2\"....simplify\r
\n" ); document.write( "\n" ); document.write( "\"4%2A5y=x%5E2\"\r
\n" ); document.write( "\n" ); document.write( "rewrite as
\n" ); document.write( "\"4p%28y-k%29=%28x-h%29%5E2\"\r
\n" ); document.write( "\n" ); document.write( " \"4%2A5%28y-0%29=%28x-0%29%5E2\"\r
\n" ); document.write( "\n" ); document.write( "so, (\"h\",\"+k\" )= (\"0\", \"0\" ), \"p=+5+\"\r
\n" ); document.write( "\n" ); document.write( "parabola is symmetric around the y-axis and so the focus lies a distance \"p\" from the center (\"0\", \"0\") along the y-axis \r
\n" ); document.write( "\n" ); document.write( "(\"0\",\"0%2Bp\")
\n" ); document.write( "(\"0\",\"0%2B5\")
\n" ); document.write( "(\"0\",\"5\")->focus\r
\n" ); document.write( "\n" ); document.write( "the distance between the focus and directrix is \"p=5+\"\r
\n" ); document.write( "\n" ); document.write( "parabola is symmetric around the y-axis and so the directrix is a line parallel to the x-axis, a distance\"+-p\" from the center left (\"0\",\"0\") x-coordinate \r
\n" ); document.write( "\n" ); document.write( "\"y=0-p\"
\n" ); document.write( "\"y=0-5\"
\n" ); document.write( "\"y=-5\"\r
\n" ); document.write( "\n" ); document.write( "the focal width is \"4p=4%2A5=20\"
\n" ); document.write( "answer:
\n" ); document.write( "Vertex: (\"0\", \"0\"); Focus: (\"0\", \"5\"); Directrix: \"y+=+-5\"; Focal width: \"20\"\r
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