2s + 3b = 19litri
5s + 1b = 15litri
Aducem la acelasi numar de sticle:
2s + 3b = 19litri | · 5
5s + 1b = 15litri | · 2
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10s + 15b = 95litri
10s + 2b = 30 litri
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13b = 65litri
b = 5
2s + 15 = 19
2s = 4litri
s = 2litri