document.write( "Question 1144229: Determine the standard form of the equation of the ellipse with center at (-4,7), a focus at (-4,11), and a vertex at (-4,12). \n" ); document.write( "
Algebra.Com's Answer #765260 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "That is an ellipse with a vertical major axis, so it looks like the
\n" ); document.write( "number zero 0, and has this standard equation:\r
\n" ); document.write( "\n" ); document.write( "\"%28x-h%29%5E2%2Fb%5E2%2B%28y-k%29%5E2%2Fa%5E2=1\"
\n" ); document.write( "where
\n" ); document.write( "(h,k) = center = (-4,7)
\n" ); document.write( " a = distance from center to vertex = 5 units
\n" ); document.write( " c = distance from center to focus = 4 units.
\n" ); document.write( " b = distance from center to covertex, found by c²=a²-b²
\n" ); document.write( " 4²=5²-b²
\n" ); document.write( " 16=25-b²
\n" ); document.write( " b²=25-16
\n" ); document.write( " b²=9
\n" ); document.write( " b=3
\n" ); document.write( "
\n" ); document.write( "\"%28x-%28-4%29%29%5E2%2F3%5E2%2B%28y-%287%29%29%5E2%2F4%5E2=1\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x%2B4%29%5E2%2F9%2B%28y-7%29%5E2%2F25=1\"\r
\n" ); document.write( "\n" ); document.write( "Edwin
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