x^2+y^2+7.2x+8.6y=2.19

解答

x^{2} + y^{2} + 7.2 x + 8.6 y = 2.19

(a, b) = (- 3.6, - 4.3), r = 5.8

求解步骤

x^{2} + y^{2} + 7.2 x + 8.6 y = 2.19

将

x^{2} + y^{2} + 7.2 x + 8.6 y = 2.19

改写为圆标准方程

(x - (- 3.6))^{2} + (y - (- 4.3))^{2} = 5. 8^{2}

因此圆的性质是:

(a, b) = (- 3.6, - 4.3), r = 5.8

x^{2} + (y - 3)^{2} = 20

(x + 20)^{2} + (y - 30)^{2} = 225

x^{2} + y^{2} + 14 x + 12 y = - 21

x^{2} + (y - 3)^{2} = 15

x^{2} + y^{2} - 2 x - 4 y + 3 = 0