The centre of circle `(x+2)^(2)+(y+4)^(2)=16`

Find the center of circle (x+2)^2+(y+4)^2=16

Find the equation of a circle which passes the centre of the circle x^(2)+y^(2)-6x =1 and concentric with the circle 2x^(2)+2y^(2)-8x +12y -1=0 .

The centre and radius of the circle (x+ 2)^(2) + (y+4)^(2) = 9 are

Equation of the circle concentric with the circle x^(2) + y^(2) + 8x + 10 y - 7 = 0 , and passing through the centre of the circle x^(2) + y^(2) - 4x - 6y = 0 ,is

Let the line segment joining the centres of the circles x^(2)-2x+y^(2)=0 and x^(2)+y^(2)+4x+8y+16=0 intersect the circles at P and Q respectively. Then the equation of the circle with PQ as its diameter is

Prove that the locus of the centre of the circle (1)/(2)(x^(2)+y^(2))+xcostheta+ysintheta-4=0 is x^(2)+y^(2)=1

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

Find the centre and radius of circle 5x^(2)+5y^(2)+4x-8y=16.

The centre of the ellipse 4x^(2) + 9y^(2) + 16x - 18y - 11 = 0 is

The number of common tangents of the circles x^(2) +y^(2) =16 and x^(2) +y^(2) -2y = 0 is :