Question

Реши систему уравнений методом подстановки:
{x−2y=−27x−12y=7

Ответ: (
;
).

Answer 1

$\left \{ {{x-2y=-2} \atop {7x-12y=7}} \right. \\\\\left \{ {{x=2y-2} \atop {7(2y-2)-12y=7}} \right.\\\\\left \{ {{x=2y-2} \atop {14y-14-12y=7}} \right.\\\\\left \{ {{x=2y-2} \atop {2y=21}} \right.\\\\\left \{ {{y=10,5} \atop {x=2*10,5-2}} \right.\\\\\left \{ {{x=19} \atop {y=10,5}} \right.\\\\Otvet:\boxed{(19;10,5)}$