Q. Write the equation in standard form for the ellipse with vertices (−9,0) and (9,0), and co-vertices (0,5) and (0,−5).
Calculate semi-major axis: Vertices are (−9,0) and (9,0), so the major axis is horizontal and the length of the major axis is 2a, where a is the semi-major axis.Calculate a: a=distance from center to vertex=9−0=9.
Calculate semi-minor axis: Co-vertices are (0,5) and (0,−5), so the minor axis is vertical and the length of the minor axis is 2b, where b is the semi-minor axis.Calculate b: b=distance from center to co-vertex=5−0=5.
Find center coordinates: The center (h,k) is at the midpoint of the vertices, which is (0,0) since the vertices are equidistant from the origin.
Standard form of ellipse equation: The standard form of the equation of an ellipse with a horizontal major axis is (x−h)2/a2+(y−k)2/b2=1. Plug in h=0, k=0, a=9, and b=5 into the equation.
Simplify the equation: The equation becomes (x−0)2/92+(y−0)2/52=1.Simplify the equation: x2/81+y2/25=1.
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