Jawaban:

1. a.) K= 46cm

b.) L= 153cm²

2. 16cm

3. 23cm

4. Nilai x = 5

Panjang sisi = 15cm

5. a.) K= 40cm

b.) L= 64cm²

Penjelasan dengan langkah-langkah:

1.Dik :

p= 14cm

l= 9cm

Dit:

K=...?

L=...?

Penyelesaian :

K= 2 × (P + L)

K= 2 × (14 + 9)

K= 2 × 23

K= 46cm

L= p × l

L= 17 × 9

L= 153 cm²

2.Dik :

K= 72

p= 20

Dit:

l= ....?

Penyelesaian:

K= 2 × p × l

72cm= 2 × 20 × l

72cm= 40 × 2 l

40 × 2 l = 72cm

2 l = 72 - 40

2 l = 32

l = 32 ÷ 2

l = 16cm

3.Dik :

K= 92cm

Dit:

s= ...?

Penyelesaian

s= K ÷ 4

s= 92 ÷ 4

s= 23cm

4.Dik :

s= 3x

K= 60cm

Dit :

Nilai x = ....

panjang sisi =....?

penyelesaian:

nilai x :

x= 4 × s = K

x= 4 × 3 = 60

x= 12 × = 60

x= 60 ÷ 12

x= 5

panjang sisi :

s= 3.(5)

s= 15cm

5.Dik:

s1= 10cm

Dit:

K= ...?

L= ...?

Penyelesaian :

K= s+s+s+s+s+s

K= 10+4+6+6+4+10

K= 40cm

L= (p×l) + (p×l)

L= (10×4) + (6×4)

L= 40 + 24

L= 64cm²