Question

3. Решите систему уравнений:
(2x – Зу = 1
3х + y = 7​

Answer 1

Ответ:(х,у)=(2,1)

Объяснение:

{2х -3у =1

{у=7-3х

2х-3(7-3х)=1

Х=2

у=7-3•2

У=1

Answer 2

$\displaystyle \left \{ {{2x-3y=1 \ \ \ \ \ \ \ \ \ \ } \atop {3x+y=7 \ \ \ \ \ \ \ |\cdot3}} \right.\\\\\\\left \{ {{2x-3y=1} \atop {9x+3y=21}} \right.\\\\\\2x+9x-3y+3y=1+21\\\\11x=22\\\\x=2 \ \ \ \ \ \ \ \ \ \ y=7-3x=7-6=1$

Ответ: {2; 1}