Question bank/JEE Main/Mathematics
JEE MainMathematicsToughStraight Lines
Equation of the line which is parallel to the line common to the
pair of lines given by
6x^2 - xy - 12y^2 = 0 and 15x^2 + 14xy - 8y^2 = 0 and the sum
of whose intercepts on the axes is 7, is
Show answer and solution
6x^2 - xy - 12y^2 = 0
(2x - 3y) (3x + 4y) = 0....(i)
and 15x^2 + 14xy - 8y^2 = 0
(5x - 2y) (3x + 4y) = 0....(ii)
Equation of the line common to (i) and (ii) is 3x + 4y = 0
Equation of any line parallel to (ii) is 3x + 4y = k or
If , then k = 12 and the equation of the
required line is 3x + 4y = 12
(2x - 3y) (3x + 4y) = 0....(i)
and 15x^2 + 14xy - 8y^2 = 0
(5x - 2y) (3x + 4y) = 0....(ii)
Equation of the line common to (i) and (ii) is 3x + 4y = 0
Equation of any line parallel to (ii) is 3x + 4y = k or
If , then k = 12 and the equation of the
required line is 3x + 4y = 12
Source: Grass-G / M-19 Mathematics Paper 28 Nov Fourth.docx
Need a video for this idea?
Scan any doubt from your notes and get a whiteboard explanation.