Today’s Lesson:
What:
Surface area of prisms and
cylinders
Why:
To calculate the surface area of both
rectangular prisms and cylinders.
Surface Area— the sum of the areas
face
of each ____________
that make up a
solid 3-D figure.
Key words for surface area:
height
SA= 2lw + 2lh + 2wh
length
Top/
Bottom
Front/
Back
Right/
Left
TOP
FRONT
BOTTOM
Net version of
rectangular
prism
RIGHT
LEFT
BACK
Rectangular PRISMS:
5 cm
1)
12 cm
SA = 256 cm²
14 cm
2)
3.5 cm
SA = 168 cm²
radius
height
SA= 2𝝿r² + 2𝝿rh
Net version
of cylinder
Top/
Bottom
Curved
Surface
CYLINDERS:
4 cm
1)
15 cm
SA ≈ 213.5 cm²
2)
2.5 cm
4.5 cm
SA = 109.9 cm²
Surface area word problems:
1) Bob is wrapping a present that is 12 inches
long, 4 inches wide, and 3 inches tall. What
is the minimum amount of wrapping paper
required?
SA = 192 in²
Surface area word problems:
2) Jane is painting a cylindrical barrel, top
and bottom included. If the barrel is 5 feet
tall with a diameter of 3 feet, how much
paint will Jane need?
SA ≈ 61.2 ft²
END OF LESSON
The next slides are student copies of the notes for this
lesson. These notes were handed out in class and
filled-in as the lesson progressed.
NOTE: The last slide(s) in any lesson slideshow
(entitled “Practice Work”) represent the homework
assigned for that day.
Rectangular Prism Net
Directions: Cut flattened shape out. DO NOT cut along the inside lines.
Once cut out, fold along the inside lines to make a rectangular prism (or
box).
Cylinder Net
Directions: Cut flattened shape out. DO NOT separate the top and bottom
circles from the rectangle. In other words, you should end up with ONE
CUT-OUT shape– NOT three separate ones!! See if you can form a
cylinder!
2.5 cm
6 cm
6 cm
13 cm.
13 cm
2.5 cm
NAME:
DATE: ______/_______/_______
Math-7 NOTES
What:
surface area of prisms and cylinders
Why:
To calculate the Volume of both rectangular prisms and cylinders.
Surface Area— the sum of the Areas of each ____________ that make up a solid 3-D figure.
Key words for surface area:
height
Net version of
rectangular
prism
length
SA= 2lw + 2lh + 2wh
Top/
Bottom
Front/
Back
Right/
Left
Rectangular PRISMS:
14 cm
2)
5 cm
1)
12 cm
3.5 cm
radius
height
SA= 2𝝿r² + 2𝝿rh
Curved
Surface
Top/
Bottom
Net version of
cylinder
CYLINDERS:
2.5 cm
4 cm
1)
2)
4.5 cm
15 cm
Surface area word problems:
1)
Bob is wrapping a present that is 12 inches long, 4 inches wide, and 3
inches tall. What is the minimum amount of wrapping paper required?
2)
Jane is painting a cylindrical barrel, top and bottom included. If the barrel
is 5 feet tall with a diameter of 3 feet, how much paint will Jane need?
DATE: _____/______/_____
NAME:___________________
Prisms:
1.
2.
3.
4.
5.
6.
7.Suzanne has a jewelry box
she wants to cover with
wallpaper to match her room.
Her box is 12 cm long, 6 cm
wide, and 5 cm high. How
much paper will she need to
cover the box?
8. What is the surface area of a
cardboard carton if it is 14
inches wide, 10 inches tall, and
16 inches long?
9. Mark had an old trunk he
wants to use in his living
room. He plans to use some
upholstery fabric to make it
look new. How much fabric
will he need to cover it if it is 4
ft. long, 2 ft wide, and 2.5 ft
tall?
cylinders:
1.
2.
3.
4.
5.
6.
7. Lynn made a kaleidoscope
that she wants to cover in
metallic wrapping paper. The
structure is 9 inches tall and
has a radius of 1.5 inches.
About how much metallic
paper will she need?
8. Louise has a large
cylindrical container that she
wants to paint. It is 4 ft. tall
and 2 ft. in diameter. What is
the surface area she will need
to paint?
9. Mr. Butterworth baked a
cake in the shape of a cylinder.
The cake had a diameter of 9
in. and a height of 5 in. He
spread chocolate icing over the
entire cake (except the
bottom). How many square
inches of icing did he use?