Pair Of Straight Lines Question 73
Question: The equation of the lines passing through the origin and having slopes 3 and $ -\frac{1}{3} $ is
Options:
A) $ 3y^{2}+8xy-3x^{2}=0 $
B) $ 3x^{2}+8xy-3y^{2}=0 $
C) $ 3y^{2}-8xy+3x^{2}=0 $
D) $ 3x^{2}+8xy+3y^{2}=0 $
Show Answer
Answer:
Correct Answer: B
Solution:
$ m_1=3,\ \ m_2=-\frac{1}{3} $ .
Hence, the lines are $ y=3x,\ y=-\frac{1}{3}x $ .
Multiplying both the lines, we get $ (y-3x)(3y+x)=0\Rightarrow 3x^{2}+8xy-3y^{2}=0. $
BETA
