document.write( "Question 589451: Write an equation for an ellipse that satisfies each set of conditions.
\n" ); document.write( "endpoints of major axis at (3, -8) and (3, 4), foci at (3, -2+2 \"+sqrt%28+5+%29+\" ) and (3, -2- \"+sqrt%28+5+%29+\" )
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Algebra.Com's Answer #374928 by lwsshak3(11628)\"\" \"About 
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Write an equation for an ellipse that satisfies each set of conditions.
\n" ); document.write( "endpoints of major axis at (3, -8) and (3, 4), foci at (3, -2+2√5) and (3, -2-√5)
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\n" ); document.write( "I will assume the 2nd given end point for the foci is (3,-2-2√5), not (3, -2-√5), as stated.
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\n" ); document.write( "Standard form of equation for an ellipse with vertical major axis: (x-h)^2/b^2+(y-k)^2/a^2=1, a>b, (h,k)=(x,y) coordinates of center.
\n" ); document.write( "For given ellipse:
\n" ); document.write( "x-coordinate of center=3
\n" ); document.write( "y-coordinate of center=-2 (by midpoint formula)
\n" ); document.write( "center: (3,-2)
\n" ); document.write( "length of vertical major axis=12=2a (from -8 to 4)
\n" ); document.write( "a=6
\n" ); document.write( "a^2=36
\n" ); document.write( "c=2√5 ( from foci)
\n" ); document.write( "c^2=20
\n" ); document.write( "c^2=a^2-b^2
\n" ); document.write( "b^2=a^2-c^2=36-20=16
\n" ); document.write( "b=4
\n" ); document.write( "Equation of given ellipse:\r
\n" ); document.write( "\n" ); document.write( "(x-3)^2/16+(y+2)^2/36=1
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