Length of latus rectum of ellipse 5{x^2} + 9{y^2} = 45 is

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10-2. Parabola, Ellipse, Hyperbola

easy

The length of the latus rectum of the ellipse $5{x^2} + 9{y^2} = 45$ is

A

$\sqrt 5 /4$

B

$\sqrt 5 /2$

C

$5/3$

D

$10/3$

Solution

(d) Here the ellipse is $\frac{{{x^2}}}{9} + \frac{{{y^2}}}{5} = 1$.

Latus rectum $ = \frac{{2{b^2}}}{a}$$ = \frac{{2 \cdot 5}}{3} = \frac{{10}}{3}$.

Standard 11

Mathematics

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