Jawabanmu

2014-05-05T12:03:09+07:00
DP : PA = 1 : 2 -> PA = 2 DP
PQ = CD . PA + AB . DP / DP + PA 
      = 12 DP + 18 DP / 3 DP   
      = 30 DP / 3 DP   = 10 cm <--