tentukan pusat dan jari jari persamaan lingkaran [tex]2 {x}^{2} + 2 {y}^{2} + 8x - 12y - 24 = 0[/tex]

2x^2 + 2y^2 +8x -12y -24 = 0. (dibagi 2)
x^2 + y^2 +4x - 6y -12 = 0
x^2 + 4x + y^2 -6y -12 = 0
(x + 2)^2 -(2)^2 +(y-3)^2 -(3)^2 -12= 0
(x+2)^2 +(y-3)^2-4-9-12= 0
(x+2)^2 +(y-3)^2 -25 = 0
(x +2)^2 +(y -3)^2 = 25
Pusat = (-2, 3) dan r = √25 = 5