Final answer:
The Aztecs faced challenges in building their capital on an island in a lake. They accommodated travel and farming by constructing causeways and using chinampas, or 'floating gardens', for agriculture.
Step-by-step explanation:
One major challenge was the fact that the city was built on an island in Lake Texcoco, which required the construction of causeways to connect it to the mainland. The Aztecs also had to find ways to accommodate travel and farming in this unique setting.
They constructed reed barges called chinampas, or 'floating gardens', which were filled with fertile soil and used for farming. These chinampas floated on the lake and were constantly irrigated with lake water. This allowed the Aztecs to grow crops and support their population even on the island.