Jawabanmu

2014-04-16T13:28:01+07:00
750 = 3X x 2X x 1X
750 = 6X3
750/6 =X3
∛125 = X
5 cm =X

3.5=15 (P)
2.5=10 (L)
1.5=5 (T) 
Lp balok = 2 x(pl+pt+lt)
             = 2 x (15.10+15.5+10.5)
             = 2 x (150+75+50)
             = 2 x (275)
             = 550 cm²

Semoga membantu :D
2014-04-16T13:43:35+07:00
V balok= p.l.t 750 = 3x.2x.1x 750 = 6x pangkat 3 750÷6 = x pangkat 3 125 = x pangkat 3 akar 125 = x 5 = x jadi, p(x), l(x), t(x) 3×5 = 15 panjang 2×5 = 10 lebar 1×5= 5 tinggi jadi, lp = 2(pl+pt+lt) lp= 2(15×10 + 15×5 + 10×5) lp=2(150+75+50) lp=2(275) lp= 550