"Bali is to the east from Jakarta."
Translation:Bali ada di timur Jakarta.
Based on observations, it seems more natural to use "ada" when you're making more of a statement, like declaring that "Bali is to the east of Jakarta". And optional words are removed more in casual conversation. Like if someone were to ask you where Bali was, and you replied "Bali di timur Jakarta" or just "di timur Jakarta".
Please correct me if I am wrong!