The straight line passing through $(-1, 1)$ and parallel to the common line of the pairs of lines given by $6x^2 - xy - 12y^2 = 0$ and $15x^2 + 14xy - 8y^2 = 0$ is:

If the lines represented by $x^2-2hxy-y^2=0$ are rotated about $(0,0)$ through an angle $\alpha$,one in the clockwise direction and the other in the counter-clockwise direction,then the combined equation of the bisectors of the angle between the lines thus obtained is

If the real pair of lines $L_1 : ax^2 + 2hxy + by^2 = 0$ represents the angle bisectors of the real lines given by $L_2 : Ax^2 + Bxy + Cy^2 + Dx + Ey + F = 0$,then which of the following is incorrect?

The joint equation of the bisectors of the angles between the lines $x=5$ and $y=3$ is

The point of intersection of the lines represented by the equation $2(x + 2)^2 + 3(x + 2)(y - 2) - 2(y - 2)^2 = 0$ is

If the bisectors of the angles between the pairs of lines given by the equations $ax^2 + 2hxy + by^2 = 0$ and $ax^2 + 2hxy + by^2 + \lambda(x^2 + y^2) = 0$ are coincident,then $\lambda = $