Question

Balok ABCD.EFGH panjangnya ( x + 3 ) cm, lebarnya x cm dan tingginya 5 cm. Jika jumlah panjang rusuknya 88 cm maka volume balok adalah... Cm³

Answer 1

Jumlah p.rusuk balok = 4.(p+l+t)
88 = 4.(x+3+x+5)
88:4 = 2x+8
22 = 2x+8
22-8 = 2x
14 = 2x
x = 14/2
x = 7

maka :
p = x+3 = 7+3 = 10 cm
l = x = 7 cm
t = 5 cm

jadi, V balok = p.l.t
= 10.7.5
= 350 cm kubik

Answer 2

Jumlah panjang rusuk = 4p + 4l + 4t
88 = 4 (x + 3) + 4 (x) + 4 . 5
88 = 4x + 12 + 4x + 20
88 = 8x + 32
8x = 88 - 32
x = 56 : 8 = 7 cm

panjang = x+3 = 7+3 = 10 cm
lebar = x = 7 cm
tinggi = 5 cm

Volume = p x l x t = 10 x 7 x 5 = 350 cm³