document.write( "Question 996230: I need help with this problem:
\n" ); document.write( "Identify the conic section whose equation is \"+x%5E2+%2B+4y%5E2+-+16y+=+0\" and write the equation in standard form.
\n" ); document.write( "Describe as completely as possible the conic section.
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Algebra.Com's Answer #614750 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
\"+x%5E2+%2B+4y%5E2+-+16y+=+0\"\r
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\n" ); document.write( "\n" ); document.write( "\"+x%5E2+%2B+4%28y%5E2+-+4y+%29=+0\"........complete square\r
\n" ); document.write( "\n" ); document.write( "\"+x%5E2%2F4+%2B+%28y%5E2+-+4y%2B2%5E2%29-4=+0\"\r
\n" ); document.write( "\n" ); document.write( "\"+x%5E2%2F4+%2B+%28y-+2%29%5E2-4=+0\"\r
\n" ); document.write( "\n" ); document.write( "\"+x%5E2%2F4+%2B+%28y-+2%29%5E2=4\"....both sides divide by \"4\"\r
\n" ); document.write( "\n" ); document.write( "\"+x%5E2%2F16+%2B+%28y-+2%29%5E2%2F4=+1\"\r
\n" ); document.write( "\n" ); document.write( "\"+x%5E2%2F16+%2B%28y-+2%29%5E2%2F4=+1\".....\"+x%5E2%2F16\" we can write as \"+%28x-0%29%5E2%2F16\" \r
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\n" ); document.write( "\n" ); document.write( "\"+%28x-0%29%5E2%2F16+%2B%28y-+2%29%5E2%2F4=+1\"\r
\n" ); document.write( "\n" ); document.write( "so, you have an ellipse that has:\r
\n" ); document.write( "\n" ); document.write( "\"h=0\",\"k=2\"
\n" ); document.write( "\"a=4\"=>semi-major axis length
\n" ); document.write( "\"b=2\"=>semi-minor axis length
\n" ); document.write( "\"c%5E2=4%5E2-2%5E2\"
\n" ); document.write( "\"c%5E2=12\"
\n" ); document.write( "\"c=sqrt%2812%29\"
\n" ); document.write( "\"c=2sqrt%283%29\"\r
\n" ); document.write( "\n" ); document.write( "the center is at (\"0\",\"2\")
\n" ); document.write( "foci : (\"c\",\"k\"), (\"-c\",\"k\")
\n" ); document.write( "(\"2sqrt%283%29\", \"2\")
\n" ); document.write( "(\"-2sqrt%283%29\", \"2\")
\n" ); document.write( "vertices: (\"a\", \"k\"), (\"4-a\", \"k\")
\n" ); document.write( " (\"4\", \"2\")
\n" ); document.write( "(\"-4\", \"2\") \r
\n" ); document.write( "\n" ); document.write( "eccentricity : \"c%2Fa=2sqrt%283%29%2F4=sqrt%283%29%2F2\" \r
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