tlg jwb please!!!....

K kubus = K persegi panjang
sisi kubus =11; Lebar balok = 10
Dit : panjang balok ?
Jawab :

K kubus = 4s = 4(11) = 44
K balok = 2(p+l) --> 44 = 2(p+10)
44 = 2p +20
2p = 44-20
2p = 24
p = 12