The circe `x ^(2) +y^(2) +8y-4 =0` cuts the real circel `x ^(2) +y^(2) +gx +4=0` orthogonally , then the value of g is-

The circle x ^(2) + y ^(2) + 8y - 4=0, cuts the real circle x ^(2) + y ^(2) + gx + 4=0 orthogonally, if g is :

If the circle x^(2)+y^(2)+2 x-2 y+4=0 cuts the circle x^(2)+y^(2)+4 x+2 f y+2 =0 orthogonally then f=

If the circle x^(2) + y^(2) + 2x - 2y + 4 = 0 cuts the circle x^(2) + y^(2) + 4x - 2fy + 2 = 0 orthogonally , then f =

If the circle x^2 + y^2 + 2x - 2y + 4 = 0 cuts the circle x^2 + y^2 + 4x - 2fy +2 = 0 orthogonally, then f =

If the circle x^2 + y^2 + 2x - 2y + 4 = 0 cuts the circle x^2 + y^2 + 4x - 2fy +2 = 0 orthogonally, then f =

If the two circles 2x^(2) +2y^(2) -3x+6y+k=0 and x^(2) +y^(2) -4x +10y +16=0 cut orthogonally, then the vlaue of k is-

If the circel x ^(2) +y^(2) +6x -2y +k=0 bisects the circumference of the circel x ^(2) +y^(2) +2x -6y-15=0, then the value of k is-

If the circle x^(2) + y^(2) + 8x - 4y + c = 0 touches the circle x^(2) + y^(2) + 2x + 4y - 11 = 0 externally and cuts the circle x^(2) + y^(2) - 6x + 8y + k = 0 orthogonally then k =

If the circles x^(2) + y^(2) - 6x - 8y + 12 = 0 , x^(2) + y^(2) - 4x + 6y + k = 0 cut orthogonally, then k =