Answer: Nine of the 13 states must vote in favor of it.
Step-by-step explanation:
The Articles of Confederation were the USA's first Constitution. When it was designed, it was done with the aim of having a weak national government and more powerful state governments.
There was no national executive or judicial branch and the legislative branch saw each of the 13 original states have 1 vote. To pass a law, 9 of these 13 states needed to vote in favor of it which made it really had to pass laws as the majority required was simply too large to be met from states that most times had differing interests.