Решите систему уравнений х^2+y^2=9 xy=2

x^2+(2/x)^2-9=0; xy=2 x^2+(4/x^2)-9=0; xy=2 x^4+4-9x^2=0; xy=2 x^4-9x^2+4=0; xy=2 D=81-16=65 x^2=(9+8,06)/2=0,47; x^2=(9-8,06)/2=6.04 x=-0.68 y=-2.94 x=0.68  y=2.94 x=-2.94 y=-0.68 x=2.94 y=0.68