Jawabanmu

2014-02-11T18:23:31+07:00
L = a*t/2
   = 6*6/2
   = 36/2
   = 18 cm

insya allah benar :)
2014-02-11T18:43:58+07:00
T dicari menggunakan pitagoras 
t = √6² + 3²
  = √36 + 9
  = √45
  = √9 x 5
  = 3 √5

L = 1/2 alas x t
  = 1/2 6 x 3√5
  = 3 x 3√5
  = 9√5