Решите системы уравнений

{x+y=-2 y^2-3x=6

{x^2+y^2=17 y-x=3

{x-y=1 x-4y^2=1

{x+2y^2=4 x-y=4

1

{x+y=-2 ⇒x=-y-2

{y^2-3x=6

y²+3y+6-6=0

y²+3y=0

y (y+3) = 0

y=0⇒x=-2

y=-3⇒x=1

(-2; 0) ; (1; -3)

2

{x^2+y^2=17

{y-x=3⇒y=3+x

x²+9+6x+x²-17=0

2x²+6x-8=0

x²+3x-4=0

x1+x2=-3 U x1*x2=-4

x1=-4⇒y1=-1

x2=1⇒y2=4

(-4; -1) ; (1; 4)

3

{x-y=1 ⇒x=1+y

{x-4y^2=1

1+y-4y²-1=0

y-4y²=0

y (1-4y) = 0

y=0⇒x=1

y=1/4⇒x=1 1/4

(1; 0) ; (1 1/4; 1/4)

4

{x+2y^2=4

{x-y=4

отнимем

2y²+y=0

y (2y+1) = 0

y=0⇒x-0=4⇒x=4

y=-0,5⇒x+0,5=4⇒x=3,5

(4; 0) ; (3,5; -0,5)