document.write( "Question 1177687: Describe, sketch and label the focus, vertex, and directrix of the parabola 4𝑦² + 8𝑦 − 8𝑥 + 7 = 0. \n" ); document.write( "
Algebra.Com's Answer #806796 by MathLover1(20855)\"\" \"About 
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\"4y%5E2+%2B+8y+%E2%88%92+8x+%2B+7+=+0\"\r
\n" ); document.write( "\n" ); document.write( "\"%284y%5E2+%2B+8y+%29=8x+-+7+\"\r
\n" ); document.write( "\n" ); document.write( "\"4%28y%5E2+%2B+2y+%29=8x+-+7+\"\r
\n" ); document.write( "\n" ); document.write( "\"%28y%5E2+%2B+2y+%29=2x+-+7%2F4\" .........complete square\r
\n" ); document.write( "\n" ); document.write( "\"%28y%5E2+%2B+2y+%2Bb%5E2%29-b%5E2=2x+-+7%2F4\".........b=2/2=1\r
\n" ); document.write( "\n" ); document.write( "\"%28y%5E2+%2B+2y+%2B1%5E2%29-1%5E2=2x+-+7%2F4\"\r
\n" ); document.write( "\n" ); document.write( "\"%28y%2B1%29%5E2-1=2x+-+7%2F4\"\r
\n" ); document.write( "\n" ); document.write( "\"%28y%2B1%29%5E2=2x+-+7%2F4%2B1\"\r
\n" ); document.write( "\n" ); document.write( "\"%28y%2B1%29%5E2=2x+-+3%2F4\"\r
\n" ); document.write( "\n" ); document.write( "\"%28y%2B1%29%5E2=2%28x+-+%283%2F4%29%2F2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"%28y%2B1%29%5E2=2%28x+-+3%2F8%29\"\r
\n" ); document.write( "\n" ); document.write( "so you have\r
\n" ); document.write( "\n" ); document.write( "\"%28y-k%29%5E2=4p%28x-h%29+\"is the standard equation for a right-left facing parabola with vertex at (\"h\",\"+k+\"), \r
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\n" ); document.write( "\n" ); document.write( "\"%28y%2B1%29%5E2=2%28x-3%2F8%29\"-> \"h=3%2F8\", \"k=-1\", \"4p=2+\"->\"p=1%2F2\"\r
\n" ); document.write( "\n" ); document.write( "vertex: (\"3%2F8\",\"-1\")\r
\n" ); document.write( "\n" ); document.write( "focus: (\"h%2Bp\",\"k\") = (\"7%2F8\",\"-1\")\r
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\n" ); document.write( "\n" ); document.write( "directrix: \r
\n" ); document.write( "\n" ); document.write( "parabola is symmetric around the \"x\"-axis and so the directrix is a line parallel to the y-axis, a distance \"-p\" from the vertex ( \"3%2F8\",\"-1\") x-coordinate \r
\n" ); document.write( "\n" ); document.write( "\"x=3%2F8-p\".........since \"p=1%2F2\"
\n" ); document.write( "\"x=3%2F8-1%2F2\"
\n" ); document.write( "\"x=3%2F8-4%2F8\"
\n" ); document.write( "\"x=-1%2F8\"\r
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