Pembahasan :
L tembereng = Lj AOB – L Δ AOB
= ⍺/360˚. πr² - a x t/2
= 90˚/360˚ . 22/7. 21 cm . 21 cm – 21 cm x 21 cm/2
= 693/2 – 441/2
= 252/2
= 126 cm²
5. Diketahui ∠OAB = 55˚ dan AB = BC.
Tentukanlah besar:
a. ∠AOB
b. ∠ACB
c. ∠ABC
Pembahasan :
L tembereng = Lj AOB – L Δ AOB
= ⍺/360˚. πr² - a x t/2
= 90˚/360˚ . 22/7. 21 cm . 21 cm – 21 cm x 21 cm/2
= 693/2 – 441/2
= 252/2
= 126 cm²
5. Diketahui ∠OAB = 55˚ dan AB = BC.
Tentukanlah besar:
a. ∠AOB
b. ∠ACB
c. ∠ABC
Editor: Dian Effendi
Sumber: Buku Kemdikbud