The combination of a verb's past participle passive with a tense of the verb, "to be" = "esse". Therefore, "amatus est" = (literally) "he is" (est) "having been loved" (amatus).
Given that this tense is formed from two words the word-order can be inverted without affecting the meaning i.e. "est amatus".
In regular-written Latin the part of "esse" is often omitted. In Q: Is Titus-Livy's "ab Urbe Condita" 26.1.9 an Example of Informal Indirect Speech?
"quas P. Cornelius habuisset decretae..." (Livy: 26.1.9) =
"which (legions) Cornelius had commanded have been assingned...".
Note "decretae" not "decretae sunt". These omissions occur often; be ready to recognise them.
In clause (iii) of this Livy quote:
"qui priore anno in Apulia foede caesus fugatusque erat." =
"which (army) had been shamefully beaten, and experienced a dreadful loss, the year before in Apulia, and had been put to flight."
Note "caesus" not "caesus erat". Further, "fugatus erat": Two pluperfect participle passives; one form of "esse". Omit both? No. To leave one emphasises that the subject (the army) is the same with both verbs.
In your example, there are two perfect passives. As a teaching aid, text books tend to include the "est" with both. Usually, at least one will be omitted.
Just to complicate the issue: the perfect passive tense can function as an aorist or "simple past" tense. Therefore, "amatus sum", can mean , "I have been loved" and also, "I was loved". This can be very helpful when translating:
"which (legions) Cornelius had commanded were assigned...".
See? Good, this "simple past" isn't it?