tolong di jawab y ka

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Jawaban :
Panjang : Lebar
= 5 : 3

80 cm = 2 × (p + l)
p + l = 80/2
p + l = 40 cm

Panjang
= 5/(5 + 3) × 40 cm
= 5/8 × 40 cm
= 25 cm

Lebar
= 3/(5 + 3) × 40 cm
= 3/8 × 40 cm
= 15 cm

Luas persegi panjang
= p × l
= 25 cm × 15 cm
= 375 cm^2
Opsi A
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Semoga Membantu

Keliling = 80cm 
2(p×l) = 80 cm
p×l = 40cm

p =  5/8 × 40 = 25 cm
l = 3/8 × 40 = 15 cm 
L = p×l
L = 25 × 15 
L = 375cm²