Jawabanmu

2014-08-17T21:22:11+07:00
(2 1) (2 1)
(1 2) (5 2)
=2.2+1.5  2.1+1.2
  1.2+2.5  1.1+2.2
=4+5  2+2
  2+10 1+4
=9    4
  12  5