Объяснение:

[tex] \frac{2x + 1}{5} = \frac{y - 1}{2} \\ 4x + 5y = 23 \\ 2(2x + 1) = 5(y - 1) \\ 4x + 5y = 23 \\ 4x + 2 = 5y - 5 \\ 4x + 5y = 23 \\ 4x - 5y = - 7 \\ 4x + 5y = 23 \\ 8x = 16 \\ x = 2 \\ y = (4 \times 2) + 5y = 23 \\ 8 + 5y = 23 \\ 5y = 15 \\ y = 3[/tex]