Question

find the surface area of the resulting cuboid when three cubes, each of the side 8cm are joined together

Answer 1

I think the way I am going to answer could be more easy
the TSA = 5asquare+4asquare+5asquare
a=8
area= 5(8*8)+4(8*8)+5(8*8)
= 320+256+320
=896cm square
is your TSA hope my answer meets your needs. and* is the sign of multiplication

Answer 2

hope it helps :)...
:)