Question

Keliling sebuah persegi panjang 44 cm.jika lebar persegi panjang 8 cm kurang dari panjangnya,luas persegi panjang adalah...

Answer 1

K = 2(p+l)
44 = 2(p+p-8)
44 = 2(2p-8)
44 = 4p -16
4p = 60
p = 15
l = 15-8= 7
L = 15 × 7 = 105

Answer 2

K = 2 (p+l)
44 = 2 (p+p-8)
44 = 2 (2p-8)
44 = 4p - 16
44 + 16 = 4p
60 = 4p
60/4 = p
15cm = p

l= p-8
 = 15-8
 = 7cm

L= pxl
  = 15 x 7
  = 105 cm²