Question

Помогите решить
x+z=o x-2z=-6666

Answer 1

$\left \{ {{x+z=0} \atop {x-2z=-6666}} \right.\\\\ \left \{ {{2x+2z=0} \atop {x-2z=-6666}} \right.$

складываем:

$\left \{ {{x+z=0} \atop {3x=-6666}} \right.\\\\ \left \{ {{z=-x} \atop {x=-2222}} \right.\\\\\left \{ {{z=2222} \atop {x=-2222}} \right.$