1 и 2. заранее спасибо

1) $\left \{ {{ 10x - y = -2}\atop {x= -y + 13}} \right.$
$\left \{ {{ 10 ( -y + 13) - y = -2}\atop {x= -y + 13}} \right.$
$\left \{ {{ -10y + 130 - y = -2}\atop {x= -y + 13}} \right.$
$\left \{ {{ -11y = - 132}\atop {x= -y + 13}} \right.$
$\left \{ {{ y = 12}\atop {x= 1}} \right.$ ,
T.o $y_{0} - x_{0} = 12 - 1 = 11$
Ответ : 11
2) $\left \{ {{ -7x - y = 8} \atop {x= -y + 40}} \right.$
$\left \{ {{ -7(-y + 40) - y = 8} \atop {x= -y + 40}} \right.$
$\left \{ {{ 7y - 280 - y = 8} \atop {x= -y + 40}} \right.$
$\left \{ {{ 6y = 288} \atop {x= -y + 40}} \right.$
$\left \{ {{y= 48} \atop {x= -8}} \right.$ ,
T.o $2x_{0} + y_{0} = 2 * (-8) + 48 = 32$
Ответ: 32