Помогите пожалуйста решить систему. {x+y = 4 ; {x^2+2xy+2y^2=17

Решите задачу:

$\left \{ {{x+y=4} \atop {x^2+2xy+2y^2=17}} \right. \\ \left \{ {{x+y=4} \atop {(x+y)^2+y^2=17}} \right. \\ \left \{ {{x+y=4} \atop {4^2+y^2=17}} \right. \\ \left \{ {{x+y=4} \atop {y^2=1}} \right. \\ \left \{ {{x_1+1=4} \atop {y_1=1}} \right. \\ \left \{ {{x_1=3} \atop {y_1=1}} \right. \\\\ \left \{ {{x_2-1=4} \atop {y_1=-1}} \right. \\ \left \{ {{x_2=5} \atop {y_2=-1}} \right.$