Jawabanmu

2014-07-19T21:11:11+07:00
DA' ^2 = 12^2 - 8^2
DA' ^2 = 144 - 64
DA' =  \sqrt{80}  = 4 \sqrt{5}

CD = 8 + 4  \sqrt{5}

L = a x t
   = (8 + 4 \sqrt{5} ) x 8
   = 64 + 32 \sqrt{5}