Найдите решение системы уравнений способом подстановки
2x+3(x+y)=11
{
7(x+3y)-6x=-59

{2х+3х+3у=11{7х+21у–6х=–59 {5х+3у=11 {х+21у=–59{х=–59–21у{5(–59–21у)+3у=11–295–105у+3у=11–102у=306у=–3х=–59–21•(–3)=4Ответ: (4; –3)

2x+3(x+y)=117(x+3y)-6y=-59********2x+3x+3y=117x+21y-6x=-59********5x+3y=11x+21=-59********5x+3y=11x=-59-21y********5(59-2y)+3y=11-295-105Y=3y=11-295-102y=11-102y=11+295-102y=306y=306:102y=3******2x=3(x+3)=112x+3x+9=115x=11-95x=2x=2:5x=0.4ответ:y=3;x=0,4