Question

5. Diketahui panjang seluruh rusuk kubus sama dengan panjang seluruh rusuk balok berukuran 10 cm x 12 cm x 8 cm. Selisih luas permukaan kubus dan balok adalah ... cm².


tolong Jawab!!!!!!!!!!!​

Answer 1

panjang rusuk

4(p + l + t) = 12 x s

4 (10 + 12 + 8) = 12 x s

4 (30) = 12 x s

120 = 12 x s

s = 120 : 12

s = 10 cm

Lp = 6 x s²

= 6 x 10 x 10

= 600 cm²

Lp = 2 (pl + pt + lt)

= 2 (10 x 12 + 10 x 8 + 12 x 8)

= 2 (120 + 80 + 96)

= 2 x 296

= 592 cm²

Selisih = Lp kubus - Lp balok

= 600 - 592

= 8 cm²

Answer 2

4(10 + 12 + 8) = 12s

12s = 4(10 + 12 + 8)

12s = 4(22 + 8)

12s = 4(30)

12s = 120

s = 120/12

s = 10 CM

LPK :

= 6s²

= 6(10)²

= 6(10(10)

= 600(10)

= 6.000 CM²

LPB :

= 2(10(12) + (10(8) + (12(8)

= 2(120 + 80 + 96)

= 2(200 + 96)

= 2(296)

= 592 CM²