Tolong dijawab dengan benar ya Pakai cara oke?

2. Sudut ABD +sudut DBC = 180
6X + 48 + 5X = 180
11X +48 = 180
11X = 132
X = 12

sudut ABD = 6X + 48
= 6(12) + 48
= 72 + 48
= 120 °

3.
9X + 6X + 45° = 180°
15X + 45° = 180 °
15X = 135°
X = 9°