If the points (k, 1), (2, -3) are conjugate w.r.t x²+y²+4x-6y-12=0 then k=

The equation to the locus of the midpoint of the chords of the circle x²+y²=r² having a constant length 2l is

Consider the circles x²+(y-1)²=9, (x-1)²+y²=25. They are such that

The parametric equations of circle x²+y²+8x-6y=0 are

The centre of the circle passing through the points (a, b), (a, -b), (a+b, a-b) is

The point diametrically opposite to the point P(1, 0) on the circle x²+y²+2x+4y-3=0 is

If the lines 3x + 4y - 14 = 0 and 6x + 8y + 7 = 0 are both tangents to a circle, then its radius is

The locus of the point which moves such that the sum of the squares of its distance from (0, a) is 2r², is

The The limiting points of the coaxal system x²+y²+2µy+9=0 are

If (2, 1 )is limiting point of the coaxal system of which x²+y²-6x-4y-3=0 is a member, then the other limiting point is