Question

5х – 2у = 9
7х + 2у = 3​

Answer 1

Ответ:

$5x - 2y = 9 \\ 7x + 2y = 3 \\ 5x - 2y = 9 \\ 2y = 3 - 7x \\ 5x - (3 - 7x) = 9 \\ 5x - 3 + 7x = 9 \\ 12x - 3 = 9 \\ 12x = 9 + 3 \\ 12x = 12 \\ x = 1 \\ 2y = 3 - 7 \times 1 \\ 2y = 3 - 7 \\ 2y = - 4 \\ y = - 2 \\ x = 1 \\ y = - 2$