Answer:
Al4C3 + 12H2O = 3CH4 + 4Al(OH)3
Step-by-step explanation:
Not sure if any explanation is needed but always start with the most complex compound. In this case it is Al(OH)3. You can see that there is 4 Aluminiums on the other side so I would start by putting a 4 next to the Al(OH)3. This now gives me 12 Hydrogens and 12 Oxygens on the right side. I put a 3 next to the CH4 to balance the Carbons on the left side. This leaves me with 12 Oxygens and 24 Hydrogens on the right side. This ends up being perfect because I can put a 12 next to the H2O.