Q. Write an equation for an ellipse centered at the origin, which has foci at (±8,0) and vertices at (±17,0).
Identify Orientation: We have:Foci: (±8,0)Vertices: (±17,0)Choose the orientation of the ellipse.Since the foci and vertices are on the x-axis, the ellipse is horizontal.
Find Value of a: We have:Center (h,k): (0,0)Vertices: (±17,0)Identify the value of a (the distance from the center to a vertex).a=∣±17−0∣= 17
Find Value of c: We have:Center (h,k): (0,0)Foci: (±8,0)Identify the value of c (the distance from the center to a focus).c=∣±8−0∣= 8
Use Relationship to Find b: We know:a=17c=8Use the relationship c2=a2−b2 to find b (the distance from the center to a co-vertex).c2=a2−b282=172−b264=289−b2b2=289−64b2=225a=170a=171
Write Standard Form: We know:(h,k)=(0,0)a=17b=15Write the standard form of the ellipse.a2(x−h)2+b2(y−k)2=1172(x−0)2+152(y−0)2=1172x2+152y2=1289x2+225y2=1
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