Notes Over 10 - 5

Surface Area

lw

hl h

l h

l w

l w

h wh w

hwhwlwlwlhlh Area hwlwlh 2Area

Surface Area

Surface Area

r Area of circle = r2

Area of circle = r2

Area of rectangle = l x w where the length is the circumference of the

circle and the width is the height. A = d h

or 2rh. .

h

SA = 2rh + 2r2

Surface AreaFind the surface area of the following figures.

1.

5 cm

12 cm

1 cm

hwlwlh 2Area

2A

2A

2A 2cm 154A

5 1 5 12 1 12

5 60 12

77

Surface AreaFind the surface area of the following figures.

5 yd3 yd

2.

SA = 2rh + 2r2

SA = 2( )( ) + 225 3 5

SA = ( )( ) + ( )30 3.14 3.1450

SA = +94.2 157 = 251.2 yd 2

Surface AreaFind the surface area of the following figures.

3 ft

4 ft

8 ft5 ft

3. The two right triangles will form

a rectangle

3

4

R1 = 3 ( 8 ) = 24R2 = 5 ( 8 ) = 40

R3 = 4 ( 8 ) = 32

SA = + + + = 108 ft 2 12 24 40 32

Pg 530 10 – 5 #1 – 7, 8 – 19 For the space figure represented by each net, find

the surface area to the nearest square unit.

1.

35 m

7 m7 m

7 m

7 m

7 m

hwlwlh 2Area

2A

2A

2A 2m 1078A

7 7 7 35 7 35

49 245 245

539

Pg 530 10 – 5 #1 – 7, 8 – 19 For the space figure represented by each net, find

the surface area to the nearest square unit.

2. 12 yd

10 yd

37.7 yd

SA = lw + 2r2

SA = ( )( ) + 2210 37.7 6

SA = ( ) + ( )377 3.1472

SA = + 377 226 = 603 yd 2

Pg 530 10 – 5 #1 – 7, 8 – 19 For the space figure represented by each net, find

the surface area to the nearest square unit.

3.

30 m

6 m9 m

6 m

9 m

6 m

hwlwlh 2Area

2A

2A

2A 2m 1008A

6 9 6 30 9 30

54 180 270

504

Pg 530 10 – 5 #1 – 7, 8 – 19 Find the surface area for each space figure. If the

answer is not a whole number round to the nearest tenth.

4. 4.8 m

4.6 m

SA = 2rh + 2r2

SA = 2( )( ) + 22

2.4 4.6 2.4SA = ( )( ) +

( )22.08 3.14 3.1411.52

SA = + 69.3312 36.1728= 105.5 m 2

Pg 530 10 – 5 #1 – 7, 8 – 19 Find the surface area for each space figure. If the

answer is not a whole number round to the nearest tenth.

5.

16 mm

12 mm

hwlwlh 2Area

2A 12 12 12 16 12 16

2A

2A 2mm 1056A

144 192 192

528

Pg 530 10 – 5 #1 – 7, 8 – 19 Find the surface area for each space figure. If the

answer is not a whole number round to the nearest tenth.

3 in

4 in

7 in5 in

6. The two right triangles will form

a rectangle

3

4

R1 = 3 ( 7 ) = 21R2 = 5 ( 7 ) = 35

R3 = 4 ( 7 ) = 28

SA = + + + = 96 in 2 12 21 35 28

Pg 530 10 – 5 #1 – 7, 8 – 19 7. The base of a rectangular prism is 3 in. by 5 in., and

the height is 11 in. Draw and label a net for the prism. Find its surface area.

11 in

3 in

5 in

5 in 3 in

hwlwlh 2Area

2A 5 3 5 11 3 11

2A

2A 2in 206A

15 55 33

103

Pg 530 10 – 5 #1 – 7, 8 – 19