1. Do Now
1) Find the area of a circle with a diameter of 10ft. Leave your answer in terms of π. [A= πr2]
2) Round to the nearest whole number.
3) How many faces are on a cube? What shape are the faces?

2. 2wl + 2lh +2wh Surface Area- the sum of the areas of its faces
Net- a 2-dimensional pattern that forms a solid when it is folded.
Net of a Rectangular Prism
width
length
height
height
length
width
Rectangular Prism
2 ( )
Area of the orange face: ______________________
width x length
Area of the blue face: ______________________
2 ( )
length x height
Area of the green face: ______________________
2 ( )
width x height
Surface Area- the sum of the areas of its faces
Surface Area of a Rectangular Prism-
2wl
+ 2lh
+2wh

3. 2wl + 2lh +2wh Surface Area of a Rectangular Prism- 2(4)(5) +2(5)(3)
Find the surface area of the rectangular prism.
5 in.
3 in.
4 in.
height
length
width
Surface Area of a Rectangular Prism-
2wl
+ 2lh
+2wh
2(4)(5)
+2(5)(3)
+2(4)(3) 40
+ 30
+ 24 94
in2

4. 2wl + 2lh +2wh Surface Area of a Rectangular Prism- 2(6)(13) +2(13)(4)
Find the surface area of the rectangular prism.
13 ft.
4 ft.
6 ft. h l w
Surface Area of a Rectangular Prism-
2wl
+ 2lh
+2wh
2(6)(13)
+2(13)(4)
+2(6)(4)
156
+ 48
308
ft2

5. Find the surface area of the rectangular prism.
12 yd.
30 yd.
9 yd. h l w
20 cm.
7 cm.
6 cm. h l w
15 ft.
2ft.
2 ft. h l w
2wl
+ 2lh
+ 2wh =
2wl
+ 2lh
+ 2wh =
2wl
+ 2lh
+ 2wh =
2(6)(20)
+2(20)(7)
+2(6)(7)
2(2)(15)
+2(15)(2)
+2(2)(2)
2(9)(12)
+2(12)(30)
+2(9)(30)
240
+ 84 60
+ 60
+ 8
216
601
cm2
128
ft2
1,476
cm2

6. How much wood does Rashid need to buy to build the box?
Rashid needs to buy some wood to build a box. He must calculate the surface area of the box to determine how much wood to buy. A diagram of the box is shown below. (2006)
2ft.
3ft.
3 ft.
How much wood does Rashid need to buy to build the box?

7. What is the best estimation, in square centimeters, for the surface area of the rectangular prism shown below? (2008)
A) 14
B) 20
C) 32
D) 48
1.9 cm
5.4 cm

8. Right Triangular Prism = wh + lw + lp + ls
Surface area of a
Right Triangular Prism
= wh + lw + lp + ls
4cm
2cm
5cm
= 3(2)
+7(3)
+7(4)
+7(5)
7cm
= 6
+ 21
+ 28
+ 35
3cm
= 90
cm2

9. Right Triangular Prism = wh + lw + lp + ls
Surface area of a
Right Triangular Prism
= wh + lw + lp + ls
6ft
3ft
8ft
= 4(3)
+10(4)
+10(6)
+10(8)
10ft
= 12
+ 40
+ 60
+ 80
4ft
= 192
ft2

10. Practice- Find the surface are of each right triangular prism.
4yd yd
5yd
6mm
8mm
9mm
5 mm
7mm 1. 2.

11. Find the surface area of each 3-dimensional object.1.
4mm.
2mm.
3mm.
Rectangular Prism h l w
12cm
8cm
10cm
15cm
5cm 2.

12. 2πr =2 h πr2 + Area = πr2 2πr Area = πr2 Area of 2 circles C = 2πr
height
height
Area = πr2
Area = πr2
Cylinder
Net of a Cylinder
Surface Area of a Cylinder
Area of 2 circles
+ Area of the rectangle
2πr =2
πr2 + h

13. Practice- Find the surface area of the cylinder
Practice- Find the surface area of the cylinder. Round your answer to the nearest tenth. h + 2
πr2
2πr
SA = 1)
7 in
3 in

14. Practice- Find the surface area of the cylinder
Practice- Find the surface area of the cylinder. Round your answer to the nearest tenth. h + 2
πr2
2πr
SA =
11 ft
5 ft 2) 3)
9 mm
14 mm

15. 4) Chris must paint the cylindrical tank shown below. (2007)
h = 5 ft h + 2
πr2
2πr
SA =
r = 2ft
A) What is the surface area of the entire tank to the nearest square foot?
B) One can of paint will cover 25 square feet. How many cans of paint must Chris purchase to paint the entire surface area of the tank?

16. 5) Joel draws a picture of his cylinder shown below. (2006)
15 cm
7 cm h + 2
πr2
2πr
SA =
Calculate the volume of Joel's cylinder. Round your answer to the nearest tenth.

17. Practice - Find the surface area of each 3-dimensional object.2.
7cm
8cm
15cm
3cm
6ft
2 ft 1.
Cylinder 3.
4cm.
2 cm.
5cm.
Rectangular Prism
Triangular Prism

18. Practice - Find the surface area of each 3-dimensional object.5.
9cm
3cm
2cm
1cm
6cm
5ft
4 ft 4.
Cylinder 6.
5cm.
8 cm.
11cm.
Rectangular Prism
Triangular Cylinder