4 (3x+y) - 1=y-2x 2 (4x-y) + 19=-x решить систему способом сложения

{4 (3x+y) - 1=y-2x

{2 (4x-y) + 19=-x

{12x+4y-1=y-2x

{8x-2y+19=-x

{12x+4y-y+2x=1

{8x-2y+x=-19

{14x+3y=1|*2

{9x-2y=-19|*3

+{28x+6y=2

+{27x-6y=-57

55x=-55|:55

x=-1

-1*14+3y=1

3y=1+14

3y=15|:3

y=5

{15+2 (x+3y) = 3 (4x+y) {2 (5x-y) - 3y=2+3 (2x+y)

{15+2x+6y=12x+3y

{10x-2y-3y=2+6x+3y

{2x+6y-12x-3y=-15

{10x-2y-3y-6x-3y=2

{-10x+3y=-15|*2

{4x-8y=2|*5

+{-20x+6y=-30

+{20x-40y=10

-34y=-20|: (-34)

y=10/17

-10x+3*10/17=-15

-10x=-15-1 13/17

-10x=-16 13/17|: (-10)

x=285/17*1/10=57/34