The pair of straight lines passing through that point `(1,2)` and perpendicular to the pair of straight lines `3x^2-8xy+5y^2=0`, is

Options

A. `(5x+3y+11)(x+y+3)=0`
B. `(5x+3y-11)(x+y-3)=0`
C. `(3x+5y-11)(x+y+3)=0`
D. `(3x_5y+11)(x+y-3)=0`

Answer

B

Explanation

The joint equation of pair of straight lines passing through the origin and perpendicular to the pair of lines `3x^2-8xy+5y^2=0` is `5x^2+8xy+3y^2=0`
Shifting the origin at `(1,2)`, we get
`5(x-1)^2+8(x-1)(y-2)+3(y-2)^2=0`
`rArr (5x+3y-11)(x+y-3)=0`
This is the joint equation of pair of lines drawn through `(1,2)` and perpendicular to pair of lines `3x^2-8xy+5y^2=0`.