Question

Помогите пожалуйста решить только 2и 10!!!))) помогите пожалуйста)на фото

Answer 1

2)

$\left \{ {{x+y=40} \atop {x-y=16}} \right. +\\\\ \left \{ {{x+y+x-y=40+16} \atop {x-y=16}} \right.\\\\ \left \{ {{2x=56} \atop {y=x-16}} \right\\\\ \left \{ {{x=28} \atop {y=28-16}} \right.\\\\ \left \{ {{x=28} \atop {y=12}} \right.\\ \\ OTBET:(28;12)$

10)

$\left \{ {{12x-7y=88} \atop {13x+14y=9}} \right. \\ \\ \left \{ {{24x-14y=176} \atop {13x+14y=9}} \right. +\\ \\ \left \{ {{24x-14y+13x+14y=176+9} \atop {13x+14y=9}} \right. \\ \\ \left \{ {{37x=185} \atop {14y=9-13x}} \right. \\ \\ \left \{ {{x=5} \atop {y=\frac{9-13*5}{14} }} \right. \\ \\ \left \{ {{x=5} \atop {y=-4}} \right. \\ \\ OTBET:(5;-4)$