pada gambar di samping besar busur POQ=40°dan luas juring OPQ=314cm kuadrat hitunglah keliling lingkaran tersebut

40°/360° x 3,14.r.r= 314 1/9.r.r= 314:3,14 1/9.r.r= 100 r= (akar) 9.100 r= (akar) 900 = 30 cm keliling: 2.3,14.30= 188,4 cm 2) 45/360.2.3,14.40= 1/8.6,28.40= 31,4 cm

Mapel : Math
Kategori Luas Juring

Penyelesaian :
Jari jari
[tex] = \sqrt{ \frac{Luas Juring}{\pi} } \div \frac{40}{360} \\ = \sqrt{ \frac{314}{3.14} } \times \frac{360}{40} \\ = \sqrt{ \frac{113.040}{125,6} } \\ = \sqrt{900} [/tex]
= 30 cm

Keliling lingkaran
= 2 × phi × r
= 2 × 3,14 × 30 cm
= 188,4 cm

Good Luck