Final answer:
The coefficients that balance the equation are 2, 12, 8, 9.
Step-by-step explanation:
The equation 2H2 + O2 → 2H₂O is balanced, but we can also write it as 4H₂ + 2O₂ → 4H₂O. The ratio of the coefficients is 4:2:4, which reduces to 2:1:2. Another balanced equation would be 22H2 + 11O2 → 22H₂O, where the coefficients are multiples of 2.