Tolong bantu di jawab yak... yg nomer 11, 13, 14, 15, 16

11.
AOB / COD = AB / CD
54°/72° = 45 cm/CD
3/4 = 45 cm/CD
15 cm x 4 = CD
60 cm = CD

13.
KOL = sudut pusat
sudut pusat = 2 x sudut keliling
KOL = 2 x 38°
KOL = 76°

14.
3x + 6x = 180°-90°
9x = 90°
x = 10°

16.
4x + 2x = 180°
6x = 180°
x = 30°

5y + 4y = 180°
9y = 180°
y = 20°