▼ Literally this is a participle in the Greek text (προσευξάμενοι, proseuxamenoi). It could be translated as a finite verb (“and they prayed and placed their hands on them”) but much smoother English results if the entire coordinate clause is converted to a relative clause that refers back to the apostles.

▼ Who prayed. The prayer indicates their acceptance and commissioning for ministry (cf. Deut 34:9).

▼ Or “laid.”