- Home
- Standard 11
- Mathematics
10-2. Parabola, Ellipse, Hyperbola
medium
The latus rectum of the hyperbola $9{x^2} - 16{y^2} - 18x - 32y - 151 = 0$ is
A
$\frac{9}{4}$
B
$9$
C
$\frac{3}{2}$
D
$\frac{9}{2}$
Solution
(d) $9{x^2} – 18x + 9 – 16{y^2} – 32y – 16 = 144$
$ \Rightarrow \frac{{{{(x – 1)}^2}}}{{16}} – \frac{{{{(y + 1)}^2}}}{9} = 1$
==> Latus rectum $ = \frac{{2{b^2}}}{a} = \frac{{2 \times 9}}{4} = \frac{9}{2}$.
Standard 11
Mathematics