How much surface area would be lost if you glued three 4cm cubes together to make a rod that is three cubes long and one cube wide?
Question
1 Answer

1. User Answers calculista
Answer:
Part 3) [tex]SA=288\ cm^2[/tex]
Part 4) [tex]64\ cm^2[/tex]
Stepbystep explanation:
Part 3) Calculate the total surface area of three 4 cm cubes
we know that
The surface area of a cube is equal to the area of its six square faces
[tex]SA=6b^2[/tex]
so
The surface area of three cubes is equal to the area of its 18 square faces
[tex]SA=18b^2[/tex]
where
b is the length side of the square face
In this problem
[tex]b=4\ cm[/tex]
so
The surface area of three cubes is
[tex]SA=18b^2[/tex]
substitute the given value
[tex]SA=18(4)^2[/tex]
[tex]SA=288\ cm^2[/tex]
Part 4) How much surface area would be lost if you glued three 4cm cubes together to make a rod that is three cubes long and one cube wide?
In this case the total surface area of the three glued 4cm cubes is equal to the area of its 14 square faces
so
The surface area lost is equal to
[tex]18b^214b^2=4b^2[/tex]
substitute
[tex]4(4)^2=64\ cm^2[/tex]