[tex]\displaystyle \left \{ {{x+4y=-6} \atop {3x-y=8}} \right.\\ \\\left \{ {{x=-6-4y} \atop {3x-y=8}} \right.\\ \\3(-6-4y)-y=8\\y=-2\\x=-6-4(-2)\\x=2\\(x,y)=(2,-2)[/tex]

Ответ:

(х; у) (2; -2)

Объяснение:

Х+4у=-6

3х-у=8

х=-6-4у

3(-6-4у)-у=8

х=-6-4у

-18-12у-у=8

х=-6-4у

-13у=26;  у=-2

х=-6-4*(-2)=2