Translation:These are the tables, and those are the chairs.
So basically the sentences "These tables" and "These are the tables" are exactly the same in Hungarian?
Well... ezek az asztalok "these tables" is not a complete sentence, while Ezek az asztalok. "These are the tables." is.
So you can usually tell the difference from the grammatical context.
Here, there is no verb, so az asztalok is likely to be the predicate = "are the tables".