Question

Розвяжіть систему методом підстановки​

Answer 1

{х + 2y = 7; 5x - y = 2;

{x = 7 - 2y; 5(7 - 2y) - y = 2;

{x = 7 - 2y; 35 - 10y - y = 2;

{x = 7 - 2y; -11y = -33;

{x = 7 - 2 × 3; y = 3;

{x = 1; y = 3.