" 2."quad Iquad s^(2)+y^(2)-4x+6y+c=0" is a circle of radim "6" find the value of "c" ."

If x^(2)+y^(2)-4x+6y+c=0 represents a circle of radius 5 then c=

If x^(2) +y^(2) -4x + 6y + c = 0 represents a circle with radius 6 then find the value of c.

If x^(2)+y^2-4x+6y+c=0 represents a circle with radius 6 then c is

If the radical axis of the circles x^(2)+y^(2)-6x-8y+c=0 and x^(2)+y^(2)-8x-6y+c=0 passes through (-1,1) then find the value of c

If the circle x^(2) + y^(2) -4x + 6y + a =0 has radius 4, find a.

When the circles x^(2)+y^(2)+4x+by+3=0 and 2(x^(2)+y^(2))+6x+4y+C=0 intersect orthogonally,then find the value of c is

If x^2+y^2-4x-6y+13=0 , then find the value of (x+y):(y-x).

If the circle x^(2)+y^(2)-4x+6y+a = 0 has radius 4 then find a.

(i) Find the equation of a circle , which is concentric with the circle x^(2) + y^(2) - 6x + 12y + 15 = 0 and of double its radius. (ii) Find the equation of a circle , which is concentric with the circle x^(2) + y^(2) - 2x - 4y + 1 = 0 and whose radius is 5. (iii) Find the equation of the cricle concentric with x^(2) + y^(2) - 4x - 6y - 3 = 0 and which touches the y-axis. (iv) find the equation of a circle passing through the centre of the circle x^(2) + y^(2) + 8x + 10y - 7 = 0 and concentric with the circle 2x^(2) + 2y^(2) - 8x - 12y - 9 = 0 . (v) Find the equation of the circle concentric with the circle x^(2) + y^(2) + 4x - 8y - 6 = 0 and having radius double of its radius.