[" 40.If "kx^(2)+10xy+3y^(2)-15x-21y+18=0],[" represents a pair of straight lines then "],[k=]

If kx^(2)+10xy+3y^(2)15x21y+18=0 represents a pair of straight lines then k=

If x^(2)- 10xy + 4y^(2) + 6x + 2y + k = 0 represents a pair of straight lines then, k=

If k x^2 + 10 xy + 3 y^2 - 15x - 21y + 18 = 0 represents a pair of straight lines. Then the value of k is :

a(x^(2)-y^(2))+xy=0 represents a pair of straight lines for

a(x^(2)-y^(2))+xy=0 represents a pair of straight lines for

If x^(2)+xy-2y^(2)+4x-y+k=0 represents a pair of straight lines, find k.

If lambda x^(2)+6xy+9y^(2)+4x+12y+3=0 represents a pair of straight lines then lambda

if lambda x^2+10xy+3y^2-15x-21y+18=0 represents a pair of straight lines. Then , the value of lambda is