Giải hệ phương trình: \(\left\{ \begin{array}{l}2x - y = 5\\{x^2} + xy + {y^2} = 7\end{array} \right.\).
A.\(\left( {x;\,y} \right) = \left( {1; - 3} \right),\left( {\frac{{18}}{7};\frac{1}{7}} \right)\)
B.\(\left( {x;\,y} \right) = \left( { - 1; - 7} \right),\left( { - \frac{{18}}{7}; - \frac{1}{7}} \right)\)
C.\(\left( {x;\,y} \right) = \left( { - 1;3} \right),\left( {\frac{{18}}{7}; - \frac{1}{7}} \right)\)
D.\(\left( {x;\,y} \right) = \left( {1;3} \right),\left( { - \frac{{18}}{7};\frac{1}{7}} \right)\)
A.\(\left( {x;\,y} \right) = \left( {1; - 3} \right),\left( {\frac{{18}}{7};\frac{1}{7}} \right)\)
B.\(\left( {x;\,y} \right) = \left( { - 1; - 7} \right),\left( { - \frac{{18}}{7}; - \frac{1}{7}} \right)\)
C.\(\left( {x;\,y} \right) = \left( { - 1;3} \right),\left( {\frac{{18}}{7}; - \frac{1}{7}} \right)\)
D.\(\left( {x;\,y} \right) = \left( {1;3} \right),\left( { - \frac{{18}}{7};\frac{1}{7}} \right)\)
Loga
Hóa Học lớp 12
