Balancing chemical equations?

this is a major issue with me.im not good with the parentheses in the chemical equations.. examples: 1) Co(OH)3 + HNO3-->Co(NO3)3+ H2O 2.) Al2(SO4)3 + Ca3(PO4)2 --> AlPO4+CaSO4 i kinda get the main points like having to check the first reactant and going from there, but my major issue is the numbers... show more this is a major issue with me.im not good with the parentheses in the chemical equations..
examples:
1) Co(OH)3 + HNO3-->Co(NO3)3+ H2O
2.) Al2(SO4)3 + Ca3(PO4)2 --> AlPO4+CaSO4

i kinda get the main points like having to check the first reactant and going from there, but my major issue is the numbers within and outside of the parenthesis. like (SO4)3 i dont understand whether the outside three applies to both the sulfur and the oxygen elements.
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