x^(4)-y^(4)

The circle x^(2)+y^(2)+4x-4y-4=0 touches

The vertex of the parabola x^(2)+y^(2)-2xy-4x-4y+4=0 is at

Equation of tangent corresponding to the normal whose equation is y=x to the circle x^(2)+y^(2)-4x-4y+4=0 is

The equation of the tangent to the circle x^(2)+y^(2)+4x-4y+4=0 which make equal intercepts on the positive coordinates, is

The equation of the tangent to the circle x^(2) + y^(2) + 4x - 4y + 4 = 0 which makes equal intercepts on the coordinates axes in given by