tolong di jawab yyiik

1. 70:40 =busur bc: busur ab
7:4
diket:panjang busur bc=35
panjang busur ab= 4/7*35=20

pakai perbandingan
Panjang Busur BC = 35
alpha BC = 70
alpha AB = 40
panjang busur BC = ? (anggap x)
35/70 = x/40
x = 20 jadi panjang busur AB = 20