no 28 yaaa,please!!!

45 derajat...maaf kalau salah;)

Mapel Matematika
Bab Sudut

ABC + DBC = 180°
ABC + 122° = 180°
ABC = 58°

ABC + BCA + CAB = 180°
58° + BCA + 42° = 180°
BCA + 100° = 180°
BCA = 80°