Q. The length of latusrectum of the ellipse $9x^{2} + 16y^{2} = 144$ is
A) 4
B) $\frac{11}{4}$
C) $\frac{7}{2}$
D) $\frac{9}{2}$
Explanation
(d)
The given equation of ellipse can be rewritten as
$\frac{x^{2}}{16} + \frac{y^{2}}{9} = 1$
Here, $a = 4,\ b = 3$
$\therefore$ Length of latusrectum $= \frac{2b^{2}}{a} = \frac{2 \times 9}{4} = \frac{9}{2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.