Find k, if one of the lines given by 6x2 + kxy + y2 = 0 is 2x + y - Maths -

Question

Find k, if one of the lines given by 6x2 + kxy + y2 = 0 is 2x + y =
0

Mayank Jha · Accepted Answer

Dear student,

Equation of pair of lines, 6x2 + kxy + y2 = 0 ------(i)Equation of a line is:2x + y = 0⇒y = -2x -----(ii)Solving (i) and (ii)6x2 + kx(-2x) + (-2x)2 = 0⇒6x2 - 2kx2 + 4x2 = 0⇒10x2 - 2kx2 = 0⇒x2 (10 - 2k) = 0⇒10 - 2k = 0⇒k = 5

Regards

Find k, if one of the lines given by 6x2 + kxy + y2 = 0 is 2x + y = 0.