### Surface Area of Rectangular Prisms

```© 2007 M. Tallman
Imagine that you
were able to take
apart this
rectangular prism
so that all faces lay
flat.
It might look
similar to this net.
Examine the
corresponding
faces of the prism
and the net.
By counting all the
square units in the
net, you will find
the surface area of
the prism.
How many units are
there?
10
6
15
15
6
10
15 + 6 + 15 + 6 + 10 + 10 = 62 units²
Imagine that you
were able to take
apart this
rectangular prism
so that all faces lay
flat.
It might look
similar to this net.
Examine the
corresponding
faces of the prism
and the net.
By counting all the
square units in the
net, you will find
the surface area of
the prism.
How many units are
there?
9
9
9
9
9
9
9 + 9 + 9 + 9 + 9 + 9 = 54 units²
Imagine that you
were able to take
apart this
rectangular prism
so that all faces lay
flat.
It might look
similar to this net.
Examine the
corresponding
faces of the prism
and the net.
By counting all the
square units in the
net, you will find
the surface area of
the prism.
How many units are
there?
15
15
9
15
9
15
15 + 9 + 15 + 9 + 15 + 15 = 78 units²
Imagine that you
were able to take
apart this
rectangular prism
so that all faces lay
flat.
6 ft
4 ft
What are the
measurements of
the net?
Find the area of
each face?
2 ft
2 ft
12 ft²
8 ft²
Examine the
corresponding
faces of the prism
and the net.
2 ft
6 ft
8 ft²
It might look
similar to this net.
4 ft
24 ft²
2 ft
12 ft²
4 ft
24 ft²
6 ft
2 ft
12 + 12 + 24 + 24 + 8 + 8 = 88 ft²
Keep in mind that
you can only see 3
faces of this
prism.
Find the area for
the visible faces
of the prism using
A = bh.
Because there are
3 “non-visible”
faces, double the
3 areas for the
visible faces.
areas.
21
topm²
4 m
28 m²
front
7 m
7 m × 4 m = 28 m²
7 m × 3 m = 21 m²
3 m × 4 m = 12 m²
right
side
12 m²
There are 3 other
faces that are not
visible.
3 m
56 m²
42 m²
+ 24 m²
122 m²
Keep in mind that
you can only see 3
faces of this
prism.
There are 3 other
faces that are not
visible.
Find the area for
the visible faces
of the prism using
A = bh.
Because there are
3 “non-visible”
faces, double the
3 areas for the
visible faces.
areas.
5 m
4 m
20top
m²
2 m
front
10 m²
5 m × 2 m = 10 m²
5 m × 4 m = 20 m²
4 m × 2 m = 8 m²
20 m²
40 m²
+ 16 m²
76 m²
Find the surface area of the rectangular prism.
front face:
5 × ___
6 = ___
30 units²
___
back face:
5 × ___
6 = ___
30 units²
___
top face:
5 × ___
7 = ___
35 units²
___
5 × ___
7 = ___
35 units²
bottom face: ___
left face:
7 × ___
6 = ___
42 units²
___
7 × ___
6 = ___
42 units²
___
214 units²
Total Surface Area:
+ ___
right face:
Find the surface area of the rectangular prism.
2 ft
3 ft
7 ft
front face:
3 × ___
7 = ___
21 ft²
___
back face:
3 × ___
7 = ___
21 ft²
___
top face:
3 × ___
2 = ___
6 ft²
___
3 × ___
2 = ___
6 ft²
bottom face: ___
right face:
2 × ___
7 = ___
14 ft²
___
2 × ___
7 = ___
14 ft²
___
82 ft²
Total Surface Area:
+ ___
left face:
Find the surface area of the rectangular prism.
front face:
12 × ___
9 = 108
___
___ m²
back face:
12 × ___
9 = 108
___
___ m²
top face:
12 × ___
8 = ___
96 m²
___
12 × ___
8 = ___
96 m²
bottom face: ___
9 m
12 m
8 m
right face:
8 × ___
9 = ___
72 m²
___
left face:
8 × ___
9 = ___
72 m²
___
Total Surface Area:
552 m²
+ ___
Find the surface area of the rectangular prism.
7 m
11 m
front face:
11 × ___
4 = ___
44 m²
___
back face:
11 × ___
4 = ___
44 m²
___
4 m top face:
bottom face:
right face:
11 × ___
7 = ___
77 m²
___
11 × ___
7 = ___
77 m²
___
7 × ___
4 = ___
28 m²
___
7 × ___
4 = ___
28 m²
___
Total Surface Area:
+ 298
___ m²
left face:
Find the surface area of this net.
8 m
8 m × 5 m = 40 m²
2 m × 5 m =
10 m²
5 m
2 m × 5 m =
10 m²
2 m
8 m × 2 m = 16 m² 2 m
5 m
2 m 8 m × 2 m = 16 m² 2 m
5 m 8 m × 5 m = 40 m² 5 m
8 m
16 m² + 16 m² + 40 m²+ 40 m² + 10 m² + 10 m² = 132 m²
3 in
6 in
3 in
6 in × 10 in
= 60 in²
3 in × 10 in
= 30 in²
10 in
3 in × 10 in
= 30 in²
Find the surface area of this net.
6 in × 3 in =
3 in
18 in²
6 in × 3 in =
18 in²
3in
6 in × 10 in
= 60 in²
10 in
6 in
30 in² + 30 in²+ 60 in²+ 60 in² + 18 in² + 18 in² = 216 in²