Jawabanmu

2014-04-26T16:46:34+07:00
Luas persegi= 72
panjang=  \sqrt{72} =6 \sqrt{2}

r= pnjang/2= 6 \sqrt{2} /2
 = 3 akar 2

tembereng= 2/7 r^2
               = 2/7 x 3 akar 2 kwadrat
               = 2/7 x 18
               = 5,14