A. r
B. r>8
C. 2
D. 2≤r≤8
The centre of the circle passing through the points (0, 0), (1, 0) and touching the circle x2+y2=9 is
Consider the circle x2+y2-4x-2y+c=0 whose centre is A(2, 1). If the point P(10, 7) is such that the line segment PA meets the circle in Q with PQ=5, then c=
The points (2k, 3k), (1, 0), (0, 1) and (0, 0) lie on a circle for
The points A(2, 3) and B(-7, -12) are conjugate points w.r. to the circle x2+y2-6x- 8y- 1=0. The centre of the circle passing through A and B and orthogonal to the given circle is
If x2+y2+6x+2ky+25=0 touches the y-axis then k=
Equation of the circle passing through (2, 0) and whose radical axis w. r. to the circle x2+y2=1 is at x=1/2 is
If the tangent from a point P to the circle x2+y2=1 is perpendicular to the tangent from P to the circle x2+y2=3, then the locus of P is
The locus of the poles of the line 2x-3y-4=0 w.r.t the circle x2+y2+2λx-16=0 is
Let AB be the chord 4x-3y +5 = 0 with respect to the circle x2+y2-2x+4y-20=0. If C= (7, 1), then the area of the triangle ABC is
The circles x2+y2=1 , x2+y2+6x-2y=1 and x2+y2-12x+4y=1 are such that