Question

Diketahui panjang busur PQ = 12 cm. Tentukan panjang busur QR !

Answer 1

Sudut PQ/Sudut Lingkaran x Keliling Lingkaran = Panjang Busur PQ
72/360 x KO = 12
36/180 x KO = 12 
18/90 x KO = 12
6/30 x KO = 12
2/10 x KO = 12
1/5 x KO = 12
KO = 12 x 5 / 1
KO = 60 cm

Sudut QR = Sudut Lingkaran - Sudut PQ = 360 - 72 = 288

Sudut QR/Sudut Keseluruhan x Keliling Lingkaran = Panjang Busur QR
288/360 x 60 = QR
144/180 x 60 = QR
72/90 x 60 = QR
36/45 x 60 = QR
12/15 x 60 = QR
4/5 x 60 = QR
240/5 = QR
48 = QR
QR = 48