Tolong ya 28 29 dan 30 pliss

^ = pangkat

28. L = 1/2.phi.r^2 = 1/2.22/7.14^2 = 1/2.22/7.196 = 308cm^2

29. L segi3 + L 1/2 lingkaran = (1/2.30.20) + (1/2.3,14.10^2) = 300 + 157 = 457cm^2

30. Volum = pphi x r^2 x t = 22/7.7^2.40 = 6160cm^3

28.
Luas ½ Lingkaran :
L = ½ × π × r × r
L = ½ × 22/7 × (28/2)²
L = ½ × 22/7 × 14 × 14
L = 22 × 2 × 7
L = 44 × 7
L = 308 cm²

Jawaban : a. 308

29.
Luas Gabungan :
L = p × l + ½ × π × r × r
L = 30 × 14 + ½ × 22/7 × (14/2)²
L = 420 + ½ × 22/7 × 7 × 7
L = 420 + 22/7 × 7 × 3,5
L = 420 + 22 × 3,5
L = 420 + 77
L = 497 cm²

Jawaban : b. 497

30.
Luas Gabungan :
L = ½ × a × t + ½ × π × r × r
L = ½ × 20 × 30 + ½ × 3,14 × (20/2) × (20/2)
L = 10 × 30 + 1,57 × 10 × 10
L = 300 + 157
L = 457 cm²

Jawaban : c. 457

Maaf Kalau Salah