yg nomer 8-10 apa? tolong saya dong yg baik soalnya tugas nya buat besok!! please yg baikk

8. - K lingkaran = pi×d = 22/7×21 = 66 dm
K persegi = 4×s = 4 × 21 = 84dm
keliling =K lingkaran+K persegi = 66 dm+84 dm = 150dm
- L1 = pi×r^2 = 22/7×21×21 = 1386 dm
L2 = s×s = 21×21 = 441 dm
L1 + L2 = 1386+441 = 1827 dm

9. - keliling = K1 + K2 = (pi×d) + (pi×d) = (22/7×21) + (3,14×10) = 66+31,4 = 97,4 cm
- Luas = L1 + L2 = (pi×r×r) + (pi×r×r) = (3,14×10,5×10,5) + (3,14×5×5) = 346,185 + 78,5 = 424,685cm

10. diket : p = 17 cm, l = 14 dm = 140 cm
- keliling = K persegi pjg + K 1/2 lingkaran = (2(p+l)) + (1/2 pi×d) = (2×17+140) + (1/2×22/7×140) = 314 + 220 = 534 cm
- Luas = L1 + L2 = (p×l) + (1/2×pi×r×r) = (17×140) + (1/2×22/7×140×140) = 2380+30800 = 33180 cm