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JEE MainMathematicsModerateStraight Lines

If px + qy + r = 0 represent a family of straight lines such
that 3p + 2q + 4r = 0 then

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Given relation is 3p + 2q + 4r = 0
⇒\Rightarrow  34p+q2+r=0\ \frac{3}{4}p + \frac{q}{2} + r = 0...........(ii)
Comparing (1) and (2) we get x=34,y=12x = \frac{3}{4},y = \frac{1}{2}
Hence we can say that these lines are concurrent at
(34,12)\left( \frac{3}{4},\frac{1}{2} \right)

Source: Grass-G / M-11 Mathematics Paper-2 1Nov.docx

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