Question

помогите решить пожалуйста​

Answer 1

$\left \{ {{x+y=-1} \atop {xy + 3x - 1 = 0}} \right. \\\\\left \{ {{x = -1-y} \atop {xy+3x-1=0}} \right. \\\\(-1-y)y+3(-1-y)-1=0\\\\y = -2\\\\x = -1 -(-2)\\\\x = 1\\\\(x , y) = (1, -2)\\\\\left \{ {{1-2=-1} \atop {1*(-2)+3*1-1=0}} \right. \\\\\left \{ {{-1=-1} \atop {0=0}} \right. \\\\(x , y) = (1 , - 2)$