Question 861939
(x+3)2/9+y2/25=1 
In the ellipse, which is the major axis-the horizon or vertical axis? Explain how you know. 
the major axis in the ellipse is the vertical axis
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Standard form of equation for an ellipse with horizontal major axis: {{{(x-h)^2/a^2+(y-k)^2/b^2=1}}} a>b
Standard form of equation for an ellipse with vertical major axis: {{{(x-h)^2/b^2+(y-k)^2/a^2=1}}}, a>b
Equation of given ellipse: {{{(x+3)^2/9+y^2/25=1}}}
note that the larger denominator is under the y-term, so given ellipse has a vertical major axis.