Conic Sections Question 168
Question: The eccentricity of the ellipse $ \frac{{{(x-1)}^{2}}}{9}+\frac{{{(y+1)}^{2}}}{25}=1 $ is
[AMU 1999]
Options:
A) 4/5
B) 3/5
C) 5/4
D) Imaginary
Show Answer
Answer:
Correct Answer: A
Solution:
$ a^{2}=b^{2}(1-e^{2}) $ , $ {\because a<b} $
$ 9=25(1-e^{2}) $
therefore $ \frac{9}{25}=1-e^{2} $
therefore $ e^{2}=\frac{16}{25} $
therefore $ e=\frac{4}{5} $ .
BETA
