(-2;-1) (-1;-2)
Объяснение:
{-(x+y)=3 {x+y=-3 {x+y=-3 {x+y=-3
{x²+y²+2xy-2xy=5 {(x²+2xy+y²)-2xy=5 {(x+y)²-2xy=5 {(-3)²-2xy=5
{x+y=-3 {x+y=-3 {x=-y-3
{-2xy=-4 {xy=2 {(-y-3)y=2 -y²-3y-2=0 y²+3y+2=0
y₁+y₂=-3 y₁y₂=2
y₁=-1 x₁=-(-1)-3=-2
y₂=-2 x₂=-(-2)-3=-1
