Pair Of Straight Lines Question 98
Question: The line $ x-2y=0 $ will be a bisector of the angle between the lines represented by the equation $ x^{2}-2hxy-2y^{2}=0 $ , if $ h= $
Options:
A) 1/2
B) 2
C) $ -2 $
D) -1/2
Show Answer
Answer:
Correct Answer: C
Solution:
Here one equation of bisector is $ x-2y=0. $
We know that both bisectors are perpendicular, therefore second bisector will be $ 2x+y=0 $ because it passes through origin.
Hence the combined equations of bisectors is given by $ (2x+y)(x-2y)=0\Rightarrow -2x^{2}+3xy+2y^{2}=0. $
Now comparing it by $ hx^{2}+3xy-hy^{2}=0 $ , we get h = -2.
BETA
