Question 949851
Equation for ellipse with center (0,0) major axis length 6, minor axis length 2, and foci on the y-axis.
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Standard form of equation for ellipse with vertical major axis: {{{x^2/b^2+y^2/a^2=1}}}, a>b, center:(0,0)
length of major axis=6=2a
a=3
a^2=9
length of minor axis=2=2b
b=1
b^2=1
Equation: {{{x^2+y^2/9=1}}}
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Write an equation for the ellipse through (-4,0) and (1,√  (15) / 2). With center (0,0) 
(solution requires more information)