a - oi
b - pasari
a + b = 33
4a + 2b = 82
a + b = 33 --> a = 33 - b
4(33 - b) + 2b = 82
132 - 4b + 2b = 82
- 2b = - 132 + 82
- 2b = - 50
b = 25 ( pasari )
a = 33 - 25 = 8 ( oi )
Proba: 25 pasari + 8 oi = 33 ( pasari + oi )
25 x 2 + 8 x 4 = 50 + 32 = 82 ( picioare )