Odpowiedź:
2x + y = 9
2y - 2x = 6
y + 2x = 9
2y - 2x =6
3y = 15 / : 3
y = 5
‐------------
2x = 9 - 5
2x = 4 / : 2
x = 2
--------
2×2 + 5 =9
L = P.