[tex]4x + y = 1 \\ x + 2y = 2 \\ \\ y = 1 - 4x \\ x + 2(1 - 4x) = 2 \\ \\ x + 2(1 - 4x) = 2 \\ x + 2 - 8x = 2 \\ - 7x = 2 - 2 \\ - 7x = 0 \\ x = 0 \\ \\ y = 1 - 4x = 1 \\ \\ Ответ: \: (0 \: ; \: 1)[/tex]
[tex]2x + 5y = 4 \: \: \: | \times 2 \\ 9x - 2y = - 31 \: \: \: | \times 5 \\ \\ 4x + 10y = 8 \\ 45x - 10y = - 155 \\ \\ 49x = - 147 \\ x = - \frac{147}{49} \\ x = - 3 \\ \\ 2 \times ( - 3) + 5y = 4 \\ - 6 + 5y = 4 \\ 5y = 4 + 6 \\ 5y = 10 \\ y = 10 \div 5 \\ y = 2 \\ \\Ответ: \: ( - 3 \: ; \: 2)[/tex]