Question

Jika luas sebuah persegi panjang 28 dm 2 dan lebarnya 40 cm, maka kelilingnya

Answer 1

Luas = p x l
28 x 100 = p x 40
p = 2800/40 = 70
keliling = 2 x ( 70 + 40 )
= 2 x 110
= 220 cm
= 22 dm
= 2,2 meter

Answer 2

28 dm² = 2800 cm²

L         = p x l
2800   = p x 40
p         = 2800/40
p         = 70 cm

K         = 2(p+l)
K         = 2(70+40)
K         = 2(110)
K         = 220 cm
K         = 2,2 m