Giải hệ phương trình: \( \left \{ \begin{array}{l}{x^2} + {y^2} + x + y = 18 \ \xy \left( {x + 1} \right) \left( {y + 1} \right) = 72 \end{array} \right. \).
A.\(\left( {x;y} \right) = \left\{ {\left( { - 3; - 4} \right),\;\left( { - 4; - 3} \right);\;\left( {4;\;2} \right),\;\left( {2;\,4} \right),\;\left( {3;\;2} \right),\;\left( {2;\;3} \right),\;\left( {3;3} \right),\;\left( { - 3;\; - 3} \right)} \right\}.\)
B.\(\left( {x;y} \right) = \left\{ {\left( {3;\,4} \right),\;\left( {4;\,3} \right);\;\left( { - 4;\;2} \right),\;\left( {2; - 4} \right),\;\left( { - 3;\; - 2} \right),\;\left( { - 2;\; - 3} \right),\;\left( {3; - 3} \right),\;\left( { - 3;\;3} \right)} \right\}.\)
C.\(\left( {x;y} \right) = \left\{ {\left( {3;\,4} \right),\;\left( {4;\,3} \right);\;\left( { - 4;\;2} \right),\;\left( {2; - 4} \right),\;\left( {3;\;2} \right),\;\left( {2;\;3} \right),\;\left( { - 3; - 3} \right),\;\left( {3;\;3} \right)} \right\}.\)
D.\(\left( {x;y} \right) = \left\{ {\left( { - 3; - 4} \right),\;\left( { - 4; - 3} \right);\;\left( { - 4;\;2} \right),\;\left( {2; - 4} \right),\;\left( {3;\;2} \right),\;\left( {2;\;3} \right),\;\left( {3; - 3} \right),\;\left( { - 3;\;3} \right)} \right\}.\)
