Metoda podstawiania
2x - 2y = 11
4x - y = 8
2x - 2y = 11
-y = 8 - 4x
2x - 2y = 11
y = 4x - 8
2x - 2(4x - 8) = 11
2x - 8x - 16 = 11
-6x = 11 + 16
-6x = 27 | /(-6)
x = -27/6
y = 4*(-27/6) - 8
x = -4 3/6
y = (-108/6) - 8
x = -4 3/6
y = -18 - 8
x = -4 3/6
y = -26