Jawabanmu

2014-07-20T09:14:11+07:00
Volume = 1/3 x La x t
400 = 1/3 x La x t
400 = 1/3 x La x 12
400 = La x 4
La = 400 : 4
La = 100 cm²

Luas segitiga
La = 100 cm² = 10 cm : 2 = 5 cm
Tinggi sisi tegak segitiga
= \/12² + 5²
= \/144 + 25
= \/169
= 13 cm

Luas permukaan limas
Lp = La + 4 x L.segitiga
Lp = 100 + (4 x (13 x 10 x 1/2))
Lp = 100 + (4 x 65)
Lp = 100 + 260
Lp = 360 cm²