Q. Write an equation for an ellipse centered at the origin, which has foci at (0,±3) and co-vertices at (±2,0).
Ellipse Orientation: We have:Foci: (0,±3)Co-vertices: (±2,0)Choose the orientation of the ellipse.Since the foci are on the y-axis, the ellipse is vertical.
Finding c: We have:Center (h,k): (0,0)Foci: (0,±3)Identify the value of c (distance from center to foci).c=(0−0)2+(3−0)2= \sqrt{0^2 + 3^2}\)= \sqrt{9}\)= 3
Finding b: We have:Center (h,k): (0,0)Co-vertices: (±2,0)Identify the value of b (distance from center to co-vertices).b=(2−0)2+(0−0)2=22+02=4=2
Finding a: We know the relationship between a, b, and c for an ellipse is c2=a2−b2. We have already found c=3 and b=2. Now we need to find a. c2=a2−b232=a2−22a0a1a2a3
Standard Form of the Ellipse: We know:(h,k)=(0,0)a=13b=2What would be the standard form of the ellipse?b2(x−0)2+a2(y−0)2=122x2+13y2=14x2+13y2=1
More problems from Write equations of ellipses in standard form using properties