Resposta:

Oi!

-x + 2y = -3

5x - 2y = -1

__________

-x = -3 - 2y

equivale a

x = 3 + 2y

5(3 + 2y) = -1

15 + 10y = -1

10y = -1 - 15

10y = -16

y = -16/10

y = -8/5

x = 3 + 2(-8/5)

x = 3 -16/5

x = -1/5

S = {-1/5 ; -8/5}

Resposta:

x=-1, y=-2

Explicação passo-a-passo:

{x+2y=-3

{5x-2y-1

{x+2y=-3

{5x-2y-1

-x+2y=-3

-x+2y+x=-3+x

2y=-3x+x

{-x+2y=-3

{5x-2y=-1

{2y=-3+x

{5x-2y=-1

5x-(-3+x)=-1

5x+3-x=-1

4x+3=-1

4x=-1-3

4x=-4

x=-1

5x-(-3+x)=-1

x=1

5(-1)-2y=-1

-5-2y=-1

-2y=-1+5

-2y=4

y=-2

5x(-1)-2y=-1

y=-2

(x,y)=(-1-2)

{-(-1)+2×(-2)=-3

{5×(-1)-2×(-2)=-1

{-3=-3

{5×(-1)-2×(-2)=-1

{(-1)+2×(-2)=-3

{5×(-1)-2×(-2)=-1

{-3=-3

{-1=-1

x-1,y-2

Resposta

x=-1,y=-2