Jawabanmu

2014-05-05T14:40:34+07:00
L = 30
P= 60
 k= 2 x ( 60 + 30 )
   = 180 cm
eh... maaf kalau salah ya?
2014-05-05T14:45:08+07:00
180 = 5/4 L x L
180 x 4/5 = L²
144 = L²
12 = L

Panjang = 5/4 x 12 = 15
keliling = 2(15+12) = 54 CM