tolong bantu kaka please

a) panjang busur AB = (120°/360°) x 2 π r
                                  = (2/6) x 2 x 3.14 x 10
                                  = 20,9 cm

b) luas juring AOB = (120°/360°) π r²
                              = (2/6) 3,14 x 10²
                              = 105 cm²

Bab Luas Juring

Mapel Matematika

Kelas VIII

 

Jawaban :

 

a.    Panjang busur AB = … ?

= a/360 x  2 x phi x r

= 120/360 x 2 x 3,14 x  10

= 20,9 cm

 

b.      Luas juring AOB  = …?

=  a/360 x phi x r x r

= 120/360 x 3,14  x  10 x 10

= 104,67 cm²