Name ———————————————————————
LESSON
11.6
Date ————————————
Practice B
For use with pages 792–799
Find the measure of a central angle of a regular polygon with the given
number of sides. Round answers to the nearest tenth of a degree,
if necessary.
1. 20 sides
2. 36 sides
3. 120 sides
4. 23 sides
Find the given angle measure for the regular dodecagon shown.
5. m∠ TWU
7. m∠ XUW
9. m∠ UWK
6. m∠ TWX
V
J
U
X
T
8. m∠ TWK
10. m∠ XWK
K
L
W
S
R
M
N
P
11. Multiple Choice Which expression gives the apothem for a regular nonagon with
side length 10.5?
5.25
A. a 5 }
tan 408
10.5
B. a 5 }
tan 208
5.25
C. a 5 }
tan 208
D. a 5 5.25 p tan 208
12. A regular hexagon has diameter 22 inches. What is the length of its apothem?
Round your answer to the nearest tenth.
Copyright © Holt McDougal. All rights reserved.
Round your answer to the nearest tenth.
Find the perimeter and area of the regular polygon. Round answers to the
nearest tenth, if necessary.
14.
15.
16.
8
LESSON 11.6
13. A regular octagon has diameter 8.5 feet. What is the length of its apothem?
5
20
17.
18.
19.
5
4.5
2.5
20. What is the area of a regular 18-gon with a side length of 8 meters? Round your
answer to the nearest tenth, if necessary.
Geometry
Chapter 11 Resource Book
363
Name ———————————————————————
LESSON
11.6
Practice B
continued
For use with pages 792–799
Date ————————————
LESSON
0.0
21. What is the area of a regular 24-gon with a side length of 10 inches? Round your
answer to the nearest tenth, if necessary.
22. What is the area of a regular 30-gon with a radius of 20 feet? Round your answer
to the nearest tenth, if necessary.
23. Find the area of a regular pentagon inscribed in a circle whose equation is given by
(x 2 4)2 1 (y 2 6)2 5 16.
24. Find the area of a regular octagon inscribed in a circle whose equation is given by
(x 2 2)2 1 (y 1 3)2 5 25.
Find the area of the shaded region. Round answers to the nearest tenth,
if necessary.
25.
26.
16
10
27.
28.
12
72° 16
In Exercises 29 and 30, use the following information.
Tiles You are tiling the floor of a hallway with tiles that are
regular hexagons as shown.
29. What is the area of each tile?
6 in.
30. The hallway has a width of 5 feet and a length of 12 feet.
At least how many tiles will you need?
31. A cup saucer is shaped like a regular decagon with a
diameter of 5.5 inches as shown.
a. What is the length of the apothem of the saucer?
Round your answer to the nearest tenth.
b. What is the perimeter and area of the saucer? Round
your answers to the nearest tenth.
364
Geometry
Chapter 11 Resource Book
5.5 in.
Copyright © Holt McDougal. All rights reserved.
LESSON 11.6
40°
Lesson 11.5, continued
18. 906.9 cm2 19. 688.8 ft2 20. 24 units; 41.6
square units 21. 45.3 units; 128 square units
15. about 88.59 m 16. about 378
17. about 9.11 m 18. about 37.31 m
22. 53.0 units; 212.1 square units 23. 41.6 units;
83.1 square units 24. 33.9 units; 72 square units
21. about 31.32 m2 22. about 70.69 in.2
23. about 110.01 in.2 24. about 219.75 cm2
25. about 12.57 cm2 26. c. 16-inch pizza
27. They all waste the same amount of paper.
Review for Mastery
1. A < 95 cm2 2. r < 7.1 yd 3. d 5 64 m
4. 423.12 m2 and 961.63 m2 5. 634.89 m2
Challenge Practice
}
50 π
1. } 2 25Ï 3 < 9.1 cm2
3
}
81 π
2. } 2 81Ï 2 < 12.7 in.2 3. 20.2 ft2
2
}
4. 36Ï 3 2 18π < 5.8 cm2
5. 1369π < 4300.8 in.2
6. a.
x
308
608
908
1208
1508
1808
y
}
3π
4
}
3π
2
}
9π
4
3π
}
15 π
4
}
b.
9π
2
Area of sector
(square inches)
27. true 28. false 29. a. 458 b. 15 in.; about
16.2 in.; 744 in.2 30. about 15.5 in.2
Practice Level B
1. 188 2. 108 3. 38 4. 15.78 5. 308 6. 158
7. 758 8. 1208 9. 908 10. 1058 11. C
12. 9.5 in. 13. 3.9 ft 14. 48 units; 166.2 square
units 15. 100 units; 688.2 square units 16. 30.4
units; 68.4 square units 17. 29.8 units; 68.4
square units 18. 60 units; 279.9 square units
19. 16.4 units; 20.5 square units 20. 1633.3 m2
21. 4557.5 in.2 22. 1247.5 ft2
23. 38.0 square units 24. 70.7 square units
25. 139.1 square units 26. 184.3 square units
27. 4.0 square units 28. 28.3 square units
29. 93.5 in.2 30. at least 93 tiles 31. a. 2.6 in.
b. 17.0 in.; 22.2 square units
Practice Level C
1. 248 2. 14.48 3. 11.38 4. 5.18 5. 10.6 in.
y
4p
6. 16.6 m 7. about 70.1 square units 8. about
400.5 square units 9. about 1014.8 square units
3p
10. 292.3 cm2 11. 187.7 in.2 12. 19.8 cm2
2p
13. 6.2 cm 14. 60 units; 247.7 square units
15. 59.6 units; 268.4 square units 16. 43.3 units;
144.0 square units 17. 72 units; 374.1 square
units 18. 73.5 units; 407.3 square units
p
0
0
60
120 180 x
Measure of arc
(degrees)
19. 74.2 units; 423.2 square units 20. always
21. always 22. never 23. about 6.9 in.2
The data appear to follow a linear pattern.
24. about 41.6 in.2 25. about 22.2% 26. $9.36
π
c. y 5 } x
40
27. a. 3 colors b. about 166.3 in.2
c. about 28 tiles
Lesson 11.6
Review for Mastery
Practice Level A
1. 308 2. 22.58 3. 98 4. 17.18 5. 608
6. 908 7. 308 8. 1208 9. 6.1 in. 10. 8.3 ft
11. 64 square units 12. about 41.6 square units
13. about 58.1 square units 14. about 187.1
square units 15. about 1039.2 square units
2
16. about 152.8 square units 17. 277.0 m
A54
25. 72.7 units; 363.3 square units 26. false
Geometry
Chapter 11 Resource Book
1. 408 2. 208 3. 908 4. P < 51.25 units;
A ø 179.37 square units 5. P < 17.63 units;
A < 21.40 square units 6. P 5 48 units;
A < 173.82 square units
Challenge Practice
1
2 1
2
180 8
180 8
1. about 110.1 cm2 2. A 5 n cos } sin }
n
n
Copyright © Holt McDougal. All rights reserved.
ANSWERS
19. about 107.68 m 20. about 31.42 m2