How long did it take the ptolemaic, seleucid, and antigonid kingdoms to coalesce and stabilize after alexander’s death?

Just a couple of decade, until 294 BC

Explanation:

Soon after the death of Alexander the Great, his generals started dividing his legacy. The strongest among them created their own dynasties.

The Kingdom of Macedon was created in 294 BC and with shorter interruption lasted until 168 BC. It wasn't a strong and rich empire, but it was unified and military advanced.  

Ptolemy created his own Ptolemaic kingdom on the soil of Egypt in 305 BC and it lasted until 30 BC. It was the wealthiest among all Hellenistic states.

The Seleucid Kingdom covered the area of Persia and was military the strongest among all Hellenistic states.

tenochtitlan (also spelled tenochtitlán), located on an island near the western shore of lake texcoco in central mexico, was the capital city and religious centre of the aztec civilization. the traditional founding date of the city was 1345 ce and it remained the most important aztec centre until its destruction at the hands of the conquering spanish led by hernán cortés in 1521 ce, which led to the final collapse of the aztec empire.