Question

the foci of an ellipse are (0,+ or - 4) and the length of the major axis is 12. How long is the minor axis?

Answer 1

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Answer 2

From the coordinates of the foci, c = 4 and the major axis is the y axis. From the length of the major axis, we obtain a = 6. Also b^2 = a^2 - c^2 =36-16= 20.

The equation of the ellipse is given by

x 2 / 2sqrt(5) + y 2 / 36 = 1