" Consider the circle "x^(2)+y^(2)-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=

Equation of the chord of the circle x^(2) + y^(2) - 4x = 0 whose mid-point is (1,0) , is

Lines are drawn through the point P(-2,-3) to meet the circle x^(2)+y^(2)-2x-10y+1=0 The length of the line segment PA,A being the point on the circle where the line meets the circle at coincident points,is 4sqrt(k) then k is

PQ is a chord of the circle x^(2)+y^(2)-2x-8=0 whose mid-point is (2, 2). The circle passing through P, Q and (1, 2) is

Find the equation of circle whose centre is the point (1,-3) and touches the line 2x-y-4=0

Let A be the centre of the circle x^(2)+y^(2)-2x-4y-20=0 . If the tangents at the points B (1, 7) and D(4, -2) on the circle meet at the point C, then the perimeter of the quadrilateral ABCD is

The line x+2y+a=0 intersects the circle x^2+y^2-4=0 at two distinct points A and B. Another line 12x-6y-41=0 intersects the circle x^2+y^2-4x-2y+1=0 at two distincts points C and D. The value of 'a' so that the line x+2y+a=0 intersects the circle x^2+y^2-4=0 at two distinct points A and B is

A line y=2x+c intersects the circle x^(2)+y^(2)-2x-4y+1=0 at P and Q. If the tangents at P and Q to the circle intersect at a right angle,then |c| is equal to

A tangent to the circle x^(2)+y^(2)=1 through the point (0, 5) cuts the circle x^(2)+y^(2)=4 at P and Q. If the tangents to the circle x^(2)+y^(2)=4 at P and Q meet at R, then the coordinates of R are