Conic Sections Question 112

Question: The equation of the hyperbola whose foci are (6, 4) and (-4, 4) and eccentricity 2 is given by

[MP PET 1993]

Options:

A) $ 12x^{2}-4y^{2}-24x+32y-127=0 $

B) $ 12x^{2}+4y^{2}+24x-32y-127=0 $

C) $ 12x^{2}-4y^{2}-24x-32y+127=0 $

D) $ 12x^{2}-4y^{2}+24x+32y+127=0 $

Show Answer

Answer:

Correct Answer: A

Solution:

Foci are (6,4) and (-4,4), $ e=2 $ and centre is $ ( \frac{6-4}{2},4 )=(1,4) $

therefore $ 6=1+ae $

therefore $ ae=5 $

therefore $ a=\frac{5}{2} $ and $ b=\frac{5}{2}(\sqrt{3}) $

Hence the required equation is $ \frac{{{(x-1)}^{2}}}{(25/4)}-\frac{{{(y-4)}^{2}}}{(75/4)}=1 $

or $ 12x^{2}-4y^{2}-24x+32y-127=0 $ .