If `ax^2+2hxy+by^2+2gx+2fy+c=0` represents a pair of lines then prove that
`triangle=abc+2fgh-af^2-bg^2-ch^2=0`.

If ax^2+2hxy+by^2+2gx+2fy+c=0 represents two parallel lines then prove that h^2=ab .

If ax^2+2hxy+by^2+2gx+2fy+c=0 represents two parallel lines then prove that af^2=bg^2 .

If ax^2+2hxy+by^2+2gx+2fy+c=0 represents a pair of parallel lines then sqrt([q^2-ac/f^2-bc])=

If ax^(2)+2hxy+by^(2)+2gx+2fy+c=0 represents a pair of parallel lines then sqrt((g^(2)-ac)/(f^(2)-bc))=

If the straight lines given by ax^(2) + 2hxy + by^(2) + 2gx + 2fy + c = 0 intersects on x -axis then show that 2fgh-af^(2)-ch^(2)=0