Question

Keliling persegi panjang 72 m lebarnya 8 m kurangnya dari panjangnya tentukan panjang dan lebarnya serta luasnya

Answer 1

Keliling= 2 x (lebar + panjang)
72 m = 2 x ( L + L+8)
72 = 2L + 2L + 16
72- 16 = 4L
56 = 4L
L = 14 CM
jadi, lebarnya = 14cm
panjang = lebar + 8 = 14 + 8 = 22 cm

luas = p x l = 14 x 22= 308 cm²

Answer 2

L = p - 8m

72 = 2 (p + l)
36 = p + l
36 = p + p - 8
44 = 2p
22 = p

l = 22 - 8 = 14 m

L = 22 x 14 = 308 m persegi