Jawaban:

5.Luas persegi = S×S

S = 38 cm

Keliling = 4×S

keliling = 4 × 38 = 152 cm

6.Luas = P× L

2.520 = 84 × L

L = 2.520 /84

L = 30 cm

Keliling = 2 × (P+L)

keliling = 2× (84+30)

keliling = 228 cm

7.keliling = 2p + 2L

200 = 2p + 2(40)

200 = 2p + 80

200-80 = 2p

120 = 2p

p = 60 cm

Luas = P× L

Luas = 60×40 = 2400 cm2

8.keliling = 4×s

s = 232/4

s = 58 cm

Luas = S×S

Luas = 58×58 = 3.364 cm2

9.Luas Trapesium = 1/2 (a+b)×t

840 = 1/2 × ( 24 + b ) × 28

840 = 14 × (24 + b)

840/14 = 24 + b

60 = 24 + b

b = 60 - 24

b = 36 cm

sisi kedua = 36cm

10.9.Luas Trapesium = 1/2 (a+b)×t

1.260 = 1/2 × ( 36+48 ) × t

1.260 = 60×t

t = 1.260/60

t = 21 cm

tinggi nya = 21 cm

11.Luas segitiga = 1/2×alas × tinggi

1 296 = 1/2 × 54 × tinggi

1 296 = 27 × tinggi

tinggi = 1296/27 = 48 cm