Triangles ABC and DBC have the following characteristics: BC is a side of both triangles∠ACB and ∠DCB are right anglesAC ≅ DC

The triangles share side BC, and AC ≅ DC. The angle between those sides is a right angle in each triangle, so the two sides and their included angle are congruent. This is the SAS congruence rule, choice SAS.

AI-written and checked against the verified answer.