{2х+у=2-0,3-0,125,
{3x+15-10y-15=7
{2x+y=1,575, /множимо на 10
{3x-10y=7
{20x+10y=15,75,
{3x-10y=7
Почленно додаємо:
23х=22,75
х=2275/2300
х=91/92
у=1,575-2х
у=1,575-2*(91/92) = 1,575-(91/46) = 1⁵⁷⁵/₁₀₀₀-1⁴⁵/₄₆ = 1²³/₄₀ - 1⁴⁵/₄₆ = - ³⁷¹/₉₂₀
(⁹¹/₉₂; - ³⁷¹/₉₂₀)