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If px+qx+r=0 represent a family fo stari...

If `px+qx+r=0` represent a family fo staright lines such that `3p+2q+4r=0` then (a) All lines are parallel (b) All lines are incosistance (c) All lines are concurrent at `((3)/(4),(1)/(2))` (d) All lines are concurrent at `(3,2)`

A

Each lines passes through the origin.

B

The lines are concurrent at the point `((3)/(4),(1)/(2))`

C

The lines are all parallel

D

The lines are not concurrent

Text Solution

Verified by Experts

Given, `px+qy+r=0` is the equation of line such that `3p+2q+4r=0`
Consider, `3p+2q+4r=0`
`implies(3p)/(4)+(2q)/(4)+r=0` (dividing the equation by `4`)
`impliesp((3)/(4))+q((1)/(2))+r=0`
`implies((3)/(4),(1)/(2))` satisfy `px+qy+r=0`
So, the lines always passes through the point `((3)/(4),(1)/(2))`.
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