When were the old and new testaments combined into the bible?
The Greek "ta biblia" (lit. "little papyrus books") was "an expression Hellenistic Jews used to describe their sacred books (the Septuagint). Christian use of the term can be traced to c. 223 CE. The biblical scholar F.F. Bruce notes that Chrysostom appears to be the first writer (in his "Homilies on Matthew", delivered between 386 and 388) to use the Greek phrase "ta biblia" ("the books") to describe both the Old and New Testaments together.
When were the old and new testaments combined into the bible and called ta tiblia?
c. 223 CE
Bible
The Old Testament canon entered into Christian use in the Greek Septuagint translations and original books, and their differing lists of texts. In addition to the Septuagint, Christianity subsequently added various writings that would become the New Testament. Somewhat different lists of accepted works continued to develop in antiquity. In the 4th century a series of synods produced a list of texts equal to the 39, 46, 51, or 54-book canon of the Old Testament and to the 27-book canon of the New Testament that would be subsequently used to today, most notably the Synod of Hippo in 393 CE. Also "c". 400, Jerome produced a definitive Latin edition of the Bible (see Vulgate), the canon of which, at the insistence of the Pope, was in accord with the earlier Synods. With the benefit of hindsight it can be said that this process effectively set the New Testament canon, although there are examples of other canonical lists in use after this time.
When were the old and new testaments combined into the bible, referred to as the Synod of Hippo?
393 CE
Bible
Bible
https://en.wikipedia.org/wiki/Bible
Development of the Christian biblical canon
https://en.wikipedia.org/wiki/Development%20of%20the%20Christian%20biblical%20canon
The Bible is not a single book but a collection of books, whose complex development is not completely understood.
Bible Development
Between 385 and 405 CE, the early Christian church translated its canon into Vulgar Latin (the common Latin spoken by ordinary people), a translation known as the Vulgate, which included in its Old Testament the books that were in the Septuagint but not in the Hebrew Bible. 
Bible Development
The synod of 393 is best known for two distinct acts. First, for the first time a council of bishops listed and approved a Christian Biblical canon that corresponds closely to the modern Catholic canon while falling short of the Orthodox canon.
Synod of Hippo
The translation was largely the work of Jerome of Stridon
Vulgate
The Bible is not a single book but a collection of books whose complex development is not completely understood. The Greek ta biblia or little papyrus books was an expression Hellenistic Jews used to describe their sacred books also known as the Septuagint. Christian use of the term ta biblia can be traced to c. 223 CE for describing the old and new testaments combined into the Bible. In addition to the Septuagint, Christianity subsequently added various writings that would become the New Testament. Between 385 and 405 CE, the early Christian church translated its canon into Vulgar Latin, a translation known as the Vulgate which was largely the work of Jerome of Stridon. The Vulgate included in its Old Testament the books that were in the Septuagint. Then, at the Synod of Hippo in 393 CE a council of bishops listed and approved a Christian Biblical canon that corresponds closely to the modern Catholic canon.