Jawabanmu

2014-06-01T20:11:05+07:00
Cara :
147 = 1/2 x a x t 
147 x 2 = 2y  x  3y
294 = 6y^2 
294/6 = y2
49 = y2
7 = y 

alas = 2y = 2 x 7 = 14 cm 
tinggi = 3y = 3 x 7 = 21 cm

2014-06-01T20:12:52+07:00
Luas = alas . tinggi : 2
147 = 2x . 3x : 2
Pindah ruas menjadi
147 x 2 = 6x²
294 = 6x²
x² = 294/6
x² = 49
x = √49
x = 7

Alas = 2x = 2.7 = 14
Tinggi = 3x = 3.7 = 21

( Note : . sama dengan x)