A. x2+y2-6x-4y+9=0, 9x2+9y2-30x-20y+25=0
B. 3 x2+3y2-16x-40y+29=0, 9x2+9y2-30x-20y+25=0
C. x2+y2-6x-4y+9=0, 9x2+9y2-30x-20y-25=0
D. x2+y2-6x-4y+9=0, x2+y2-10x+50y-25=0
If 4y=x+7 is diameter of the circumscribing circle of the rectangle ABCD and A(-3, 4), B(5, 4), then the area of the rectangle is
The polar of the point(2t, t-4) w.r.t the circle x2+y2-4x-6y+1=0 passes through the point
The locus of midpoints of chords of the circle x2+y2=2r2 subtending a right angle at the centre of the circle is
The centres of the circles are (a, c) and (b, c) and their radical axis is the y-axis. The radius of one of the circle is r. The radius of the other circle is
The tangents drawn from the origin to the circle x2+y2-2rx-2hy+h2=0 are perpendicular if
If x2+y2-2x+3y+k=0 and x2+y2+8x-6y-7=0 cut each orthogonally, the value of k must be
The equation of the circle passing through the intersection of the circles x2+y2=2ax and x2+y2=2by and having its centre on the x/a-y/b=2 is
If O is the origin and OP, OQ are the tangents to the circles x2+y2+2gx+2fy+c=0 then the circumcentre of the ΔOPQ is
If a circle passes through the point (a, b) and cuts the circle x2+y2=k2 orthogonally, the equation of the locus of its centre is
Let A be the centre of the circle x2+y2-2x-4y-20=0. Suppose that the tangent at the point B(1, 7) and D(4, -2) on the circle meet at the point C. The area of the quadrilateral ABCD is