Jawabanmu

2014-04-28T14:17:09+07:00
A. V= plt
     = 4.3.t = 24
t = 2

LP = 4x3x2 = 24
     = 3x2x2 = 12
     = 4x2x2 = 16
LP = 52

b. V = plt
     = 9.7. t = 315
t = 5

LP = 9x7x2 = 126
     = 5x7x2 = 70
     = 9x5x2 = 90
= 286

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2014-04-28T14:19:53+07:00
A. Diket =
V = 24 cm³, p = 4 cm, l = 3 cm
t = V : p x l
= 24 cm³ : 4 cm x 3 cm
= 2 cm
luas seluruh permukaan balok = (p x l x 2) + (p x t x 2) + (l x t x 2)
= (4 cm x 3 cm x 2) + (4 cm x 2 cm x 2) + (3 cm x 2 cm x 2)
= 24 cm² + 16 cm² + 12 cm²
= 52 cm²

b. Diket =
V = 315 cm³, p = 9 cm, l = 7 cm
t = V : p x l
= 315 cm³ : 9 cm x 7 cm
= 5 cm
luas seluruh permukaan balok = (p x l x 2) + (p x t x 2) + (l x t x 2)
= (9 cm x 7 cm x 2) + (9 cm x 5 cm x 2) + (7 cm x 5 cm x 2)
= 126 cm² + 90 cm² + 70 cm²
= 286 cm²
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