Question 470793
Write an equation in standard form of an ellipse that is 10 units high and 8 units wide. The center of the ellipse is (0,0)
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Standard form of ellipse with vertical major axis and center at the origin: 
x^2/b^2+y^2/a^2=1, a>b
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2a=length of major axis=10
a=5
a^2=25
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2b=length of minor axis=8
b=4
b^2=16
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Equation: x^2/16+y^2/25=1
See graph below as a visual check on the answer
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y=±(25-25x^2/16)^.5
{{{ graph( 300, 300, -10, 10, -10, 10,(25-25x^2/16)^.5,-(25-25x^2/16)^.5) }}}