Question

{█(х-у=2,
х^2-ху+у^2=7 помогите решить систему уравнений

Answer 1

$left { {{x-y=2} atop {x^{2}-xy+y^{2}=7}} right. left { {{x-y=2} atop {(x-y)^{2}+xy=7}} right. left { {{x-y=2} atop {2^{2}+xy=7}} right. left { {{x=2+y} atop {xy=7-4}} right. left { {{x=2+y} atop {(y+2)y=3}} right. \ y^{2}+2y-3=0 \ D=1+3=4 \ y_{1}=-1+2=1 - textgreater x_{1}=2+y_{1}=2+1=3 \ y_{2}=-1-2=-3 - textgreater x_{2}=2+y_{2}=2-3=-1$
                   Ответ: (3;1) и (-1;-3)