tolong dong kak, pake cara yaww :D

BCA = 180 - 100.
BCA = 80.

ABC = 180 - (BCA + CAB).
ABC = 180 - (80 + 48).
ABC = 180 - 128.
ABC = 52.

2x - 16 + ABC = 180.
2x - 16 + 52 = 180.
2x = 180 + 16 - 52.
2x = 144.
x = 144/2.
x = 72.

Jawaban : D.