"I do not like the tables."
Translation:Nem szeretem az asztalokat.
Az asztalokat nem szeretem is fine and almost indistinguishable in meaning from Nem szeretem az asztalokat.
I'm pretty sure they began by writing/choosing the Hungarian sentences, and provided English translations for them, but didn't always account for all the different ways those English sentences could be translated back into Hungarian.
A bit of a translating note.
"I do not like the tables." sounds specific to me. Talking about some specific tables that are ugly, not properly set, etc. This kind of "I don't like" I would translate as "Nem tetszik" - it does not please me literally. So, the translation would be:
"Nem tetszenek az asztalok."
And the general "I do not like tables", which means I have a general issue with tables, would be translated as:
"Nem szeretem az asztalokat."
This is a mix of two things.
"The tables", literally, is "az asztalok". Here, "az" (or "a", depending on the starting letter of the following word) is the same kind of "fixed" article as "the" is in English - you either put it there or don't but you don't inflect it in any way.
On the other hand, there is "Those tables", why translates to "azok az asztalok". Here, the first "az" serves as a demonstrative pronoun/adjective, and just like in English, it always inflects as if it was a pronoun, including cases (hence, "azokat" in this sentence). Also, because of the way the definite article developed from the demonstrative pronoun/adjective, you have to include it here. So in this case, the sentence would be "Nem szeretem azokat az asztalokat."