X+y+2=-5 - 2x-y+2=-1 x-2y-2=0 solve algebraically

x+y+2=-5 - 2x-y+2=-1 x-2y-2=0 solve algebraically

x+y+2=-5 equation 1

-2x-y+2=-1 equation 2

x-2y-2=0 equation 3

Add equation 1 + 2 + 3

x+y+2=-5 + - 2x-y+2+1 + x-2y-2

x+y+2 = - 7+2+1-2x+x+y

x+y+2 = - 4-x+y

x+y+2+4+x-y = 0

2x+6 = 0

2x = - 6

divide both side by 2

x = - 3

from equation 1 insert x

x+y+2=-5

since x=-3

then, - 3+2+y = - 5

-1+y = - 5

y = - 5+1

y = - 4