tolong dijawab no 15&16......

No.15

Dik:r :21 cm
sp:72°
ssp:360°
π : 22/ 7
Dit : Panjang busur PQ?

Jawab!
Cari dulu Keliling lingkaran nya....
Keliling linggkaran =2×π×r
=2×22/7× 21
=132 cm
Sp/ssp = pb/Kelililing lingkaran

72°/360° = pb/132

1/5 = pb/132

1/5×132 = pb

132/5 = pb

26,4 Cm = Pb

Jadi jawaban nya B.26,4 cm