Question

Помогите пожалуйста
...............................

Answer 1

$\displaystyle \left \{ {{x-y+1=0} \atop {x+2y+4=0}} \right. \\\\\left \{ {{x=y-1} \atop {x+2y+4=0}} \right. \\\\y-1+2y+4=0\\y=-1\\x=-1-1\\x=-2\\(x,y)=(-2,-1)$