bantuin ya...pake cara

maaf yang no.1 aku gak bisa
maaf ya..

1. 180° - 90° - 45° = 45°
180° - 90° - 30° = 60°

180° - 60° - 45° = 75° (c)

2. 9/15 = CE/20
15CE = 180
CE = 12

BE = 20-12 = 8 (a)

3. 40° ←→ 2.000
120° ←→ (?) 120/40 × 2.000 = 6000 (d)