The pairs of straight lines `ax^(2)-2hxy-ay^(2)=0` and `hx^(2)-2axy-gy^(2)=0` are such that

If the pairs of straight lines ax^(2)+2hxy-ay^(2)=0 and bx^(2)+2gxy-by^(2)=0 be such that each bisects the angles between the other, then

If the pairs of straight lines ax^(2)+2hxy-ay^(2)=0 and bx^(2)+2gxy-by^(2)=0 be such that each bisects the angles between the other, then

If the pairs of straight lines ax^(2)+2hxy-ay^(2)=0 and bx^(2)+2gxy-by^(2)=0 be such that each bisects the angles between the other, then

If the pairs of straight lines ax^2+2hxy-ay^2=0 and 'bx^2+2gxy-by^2=0 be such that each bisects the angles between the other , then

If pair of st lines ax^(2)+2hxy-ay^(2)-ay^(2)=0 and bx^(2)+2gxy-by^(2)=0 be such that each bisects the angle between the other then

The pair of lines a^(2)x^(2)+2h(a+b)xy+b^(2)y^(2)=0 and ax^(2)+2hxy+by^(2)=0 are

If two pairs of straight lines having equations y^(2)+xy-12x^(2)=0 and ax^(2)+2hxy+by^(2)=0 have one line common, then a =

If the bisectors of the angles between the pairs of lines ax^(2)+2hxy+by_(2)=0 and ax^(2)+2hxy+by^(2)+lamda(x^(2)+y^(2))=0 are coincident, then: lamda=