I.
6. K = 32 cm
p = 9 cm
l = ?
K = 2p + 2l
32 cm = (2 × 9 cm) + 2l
32 cm = 18 cm + 2l
2l = 32 cm - 18 cm
2l = 14 cm
l = 7 cm -> d.
7. a = 9cm
b = 12 cm
K = ?
c² = a² + b²
c² = 9² + 12²
c² = 81 + 144
c² = 225
c = √225
c = 15 cm
K = a + b + c
K = 9 cm + 12 cm + 15 cm
K = 36 cm -> d.
8. K = 69 cm
s = ?
s = 69 cm ÷ 3
s = 23 cm -> c.
9. AB = 10 cm
BC = 4 cm
DE = 3 cm
EF = 3 cm
K = ?
AG = BC = 4 cm
FG = DE = 3 cm
DG = EF = 3 cm
CD = AB - DG
CD = 10 cm - 3 cm
CD = 7 cm
K = AB + BC + CD + DE + EF + FG + AG
K = 10 cm + 4 cm + 7 cm + 3 cm + 3 cm + 3 cm + 4 cm
K = 34 cm -> b.
10. K = ?
AB = 8 cm
AD = 8 cm
BC = 10 cm
CD = 8 cm + 6 cm
CD = 14 cm
K = AB + BC + CD + AD
K = 8 cm + 10 cm + 14 cm + 8 cm
K = 40 cm -> c.
II.
1. K = ?
a. K = 30 + 24 + 14
K = 68 cm
b. K = (2 × 12) + (2 × 10)
K = 24 + 20
K = 44 cm
2. p = 1 m = 100 cm
l = 0,5 m = 50 cm
panjang pita = ?
panjang pita = K
panjang pita = (2 × 100) + (2 × 50)
panjang pita = 200 + 100
panjang pita = 300 cm
3. s = 10 m
jarak antar pohon = 2 m
jumlah pohon = ?
jumlah pohon = K ÷ jarak antar pohon
jumlah pohon = (4 × 10) ÷ 2
jumlah pohon = 40 ÷ 2
jumlah pohon = 20
4. p = ?
2p + 2l = 4s
2p + (2 × 40) = 4 × 25
2p + 80 = 100
2p = 100 - 80
2p = 20
p = 10 cm
