If `ax^(2)+by^(2)+2fy+c=0` `(a!=0)` represents pair of lines then

IF the equation x^(2) + y^(2) + 2gx + 2fy + 1 = 0 represents a pair of lines, then

If the equation ax^(2)+ay^(2)+2gx+2fy+c=0 represents a pair of lines then

If the equation ax^(2)+hxy+by^(2)+4gx+6fy+4c=0 represents a pair of lines then

If ax^(2)-y^(2)+4x-y=0 represents a pair off lines then a=

If the equation ax^(2)-6xy+y^(2)+2gx+2fy+c=0 represents a pair of lines whose slopes are m and m^(2), then sum of all possible values of a is-

If the equation ax^(2)+by^(2)+cx+xy=0 represents a pair of line, then

If the equation x^(2)+2hxy+2fy+c=0 represents a pair of lines, then

Let the equation ax^(2)+2hxy+by^(2)=0 represents a pair of straight lines then the angle theta - between the lines is given by cos theta=

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