This demonstration teaching was held on April 22, 2022 in the section GOTO B, at 10:00 until 11:45 in the morning. The lesson started with the preliminaries and the discussion of a Try This problem on the topic in the previous meeting. After which, the teacher introduced another topic to the class by unlocking some terms through giving definition and illustration. The class then learned new set of theorems which would help them in proving problems on triangle congruence.