Does `x^(2)+y^(2)=0` represent a pair of straight lines

Let ax^(2)+2hxy+by^(2)=0 represent a pair of straight lines. Then show that the equation of the pair of straight lines. Passing through (x_(0),y_(0)) and parallel to the given pair of lines is a(x-x_(0))^(2)+2h(x-x_(0))(y-y_(0))+b(y-y_(0))^(2)=0

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

Prove that the equation 2x^(2)+xy-6y^(2)+7y-2=0 represents a pair of straight lines.

The equation of lines 2x^(2)+3xy-2y^(2)+3x-9y-9=0 represents a pair of straight lines, the distance of the point of intersection from the origin, is

Prove that the equation 3x^(2)+7xy+2y^(2)+5x+5y+2=0 represents a pair of straight lines. Find the point of intersection. Also find the angle between them.

Does the equation x^(2)+xy+y^(2)=0 represent a pair of lines?

The condition that the equation ax^2+by^2+c(x+y)=0 to represents a pair of straight lines is