a)
2x + 3y = 1 /·5
3x + 5y = 4 /·(-3)
10x + 15y = 5
-9x - 15y = -12
----------------------- +
x = -7
5y = 4 - 3x = 4 - 3 · (-7) = 4 + 21 = 25
5y = 25 /:5
y = 5
{x = -7
{y = 5
b)
9x + 6y = 1 /·(-4)
12x + 8y = 3 /·3
-36x - 24y = -4
36x + 24y = 9
----------------------- +
0 = 5, sprzeczność, brak rozwiązania
0 ≠ 5