" c) "2x^(2)+ax-a^(2)=0quad (" CBSE "2014)

The circles x^(2) +y^(2) + 2ax +c =0 and x^(2) +y^(2) +2bx +c =0 have no common tangent if

Show that the circles x^(2)+y^(2)+2ax+c=0 and x^(2)+y^(2)+2by+c=0 touch each other if 1/(a^(2))+1/(b^(2))=1/c

Show that the circles x^(2) +y^(2) + 2ax + c=0 and x ^(2) + y^(2) + 2by + c=0 to touch each other if (1)/(a^(2)) + (1)/( b^(2)) = (1)/( c )

Area of quadrilateral formed by two pair of lines a^(2)x^(2)-b^(2)y^(2)-c(ax+by)=0 and a^(2)x^(2)-b^(2)y^(2)+c(ax-by)=0 is

The ratio of the roots of the equation ax^(2)+bx+c=0 is same equation Ax^(2)+Bx+C=0. If D_(1) and D_(2) are the discriminants of 0. If D_(1) and D_(2) are the ax^(2)+bx+C=0 and Ax^(2)+Bx+C=0 respectively,then D_(1):D_(2)