Система: ху+х=56 ху+у=54
X(y+1)=56 xy+y=54 x=56/(y+1) 56y/(y+1) + y = 54 56y + y² + y = 54y+ 54 y² + 3y - 54 = 0 D=9+216 = 225 y₁=(-3+15)/2=6 y₂ = (-3-15)/2 = -9 x₁= 56/(6+1) = 8 x₂ = 56/(-9+1) = -7 Ответ; (8; 6) ; (-7;-9)