Question

The foci of an ellipse are at (-3, 0) and (3, 0). If the eccentricity of the ellipse is 1/2, then the equation of the ellipse is:

• A. $\dfrac{x^2}{25} + \dfrac{y^2}{16} = 1$
• B. $\dfrac{x^2}{16} + \dfrac{y^2}{7} = 1$
• C. $\dfrac{x^2}{16} + \dfrac{y^2}{25} = 1$
• D. $\dfrac{x^2}{36} + \dfrac{y^2}{16} = 1$
• E. $\dfrac{x^2}{36} + \dfrac{y^2}{27} = 1$

Hint:

For an ellipse: $c = ae$, $b^2 = a^2(1 - e^2)$. Remember $a$ > $b$ > $0$ when the major axis lies along the $x$-axis.

Answer 1

Answer: (E)