Jawabanmu

2014-06-22T05:56:07+07:00
AC^2 = 12^2 + 9^2
= 144 + 81
= 225
AC = √225 = 15 cm
AG^2 = 15^2 + 8^2
= 225 + 64
= 289
AG = √289 = 17 cm
1 5 1
2014-06-22T07:01:45+07:00
AG = √(12²+9²+8²)
      = √(144+81+64)
      = √289
      = 17
Jadi, diagonal balok ABCD.EFGH yaitu AG = 17 cm