Conic Sections Question 527
Question: Equation of the parabola whose directrix is $ y=2x-9 $ and focus (-8, -2) is
Options:
A) $ x^{2}+4y^{2}+4xy+16x+2y+259=0 $
B) $ x^{2}+4y^{2}+4xy+116x+2y+259=0 $
C) $ x^{2}+y^{2}+4xy+116x+2y+259=0 $
D) None of these
Show Answer
Answer:
Correct Answer: B
Solution:
Let any point on it be (x, y), then from definition of parabola, we get $ \frac{\sqrt{{{(x+8)}^{2}}+{{(y+2)}^{2}}}}{| \frac{2x-y-9}{\sqrt{5}} |}=1 $
Squaring and after simplification, we get $ x^{2}+4y^{2}+4xy+116x+2y+259=0 $ .
BETA
