A.\(I\left( { - 1;\,\,2} \right),\,\,R = 3\)
B.\(I\left( {1; - 2} \right),\,\,R = 3\)
C.\(I\left( {1;\, - 2} \right),\,\,R = 9\)
D.\(I\left( {2;\, - 4} \right),\,\,R = 9\)

A.\({x^2} + {y^2} + 2x - 20 = 0\)
B.\({x^2} + {y^2} - 4x + 7y - 8 = 0\)
C.\({x^2} + {y^2} - 6x - 2y + 9 = 0\)
D.\({x^2} + {y^2} - 2x + 6y = 0\)

A.\({x^2} + {y^2} + 6x - 10y + 30 = 0\)
B.\({x^2} + {y^2} - 6x + 10y - 30 = 0\)
C.\({x^2} + {y^2} - 6x + 10y + 30 = 0\)
D.\({x^2} + {y^2} + 6x - 10 - 30 = 0\)

A.\({a^2} + {b^2} - c > 0\)
B.\({a^2} + {b^2} - c \ge 0\)
C.\({a^2} + {b^2} - 4c > 0\)
D.\({a^2} + {b^2} - 4c \ge 0\)

A.\(1\)
B.\(2\)
C.\(3\)
D.\(4\)

A.\({\left( {x - 2} \right)^2} + {\left( {y - 4} \right)^2} = \sqrt {10} \)
B.\({\left( {x + 2} \right)^2} + {\left( {y + 4} \right)^2} = 10\)
C.\({\left( {x - 2} \right)^2} + {\left( {y - 4} \right)^2} = 10\)
D.\({\left( {x + 2} \right)^2} + {\left( {y + 4} \right)^2} = 2\sqrt 5 \)

A.\(\left( C \right):\,\,{\left( {x + 6} \right)^2} + {\left( {y - 7} \right)^2} = 9\)
B.\(\left( C \right):\,\,{\left( {x + 6} \right)^2} + {\left( {y - 7} \right)^2} = 81\)
C.\(\left( C \right):\,\,{\left( {x + 6} \right)^2} + {\left( {y - 7} \right)^2} = 89\)
D.\(\left( C \right):\,\,{\left( {x + 6} \right)^2} + {\left( {y - 7} \right)^2} = \sqrt {89} \)

A.\(\left( C \right)\) có tâm \(I\left( { - 1;\,\, - 2} \right)\)
B.\(\left( C \right)\) có bán kính \(R = 5\)
C.\(\left( C \right)\) đi qua điểm \(M\left( {2;\,\,2} \right)\)
D.\(\left( C \right)\) đi qua \(A\left( {1;\,\,1} \right)\)

A.\({x^2} + {y^2} + 2x - 6y - 22 = 0\)
B.\({x^2} + {y^2} - 2x - 6y - 22 = 0\)
C.\({x^2} + {y^2} - 2x - 6y + 22 = 0\)
D.\({x^2} + {y^2} - 2x + 6y + 22 = 0\)

A.\(0\)
B.\(1\)
C.\(2\)
D.\(3\)