Name ________________________________________ Date __________________ Class__________________
LESSON
1-5
Practice B
Using Formulas in Geometry
Use the figures for Exercises 1–3.
1. Find the perimeter of triangle A. _______________
2. Find the area of triangle A. _______________
3. Triangle A is identical to triangle B.
Find the height h of triangle B.
_______________
Find the perimeter and area of each shape.
5. rectangle with length (x + 3) and width 7
4. square with a side 2.4 m in length
_________________________________________
________________________________________
6. Although a circle does not have sides, it does have a perimeter.
What is the term for the perimeter of a circle?
_______________
Find the circumference and area of each circle.
7.
8.
________________________
10. The area of a square is
9.
_________________________
________________________
1 2
in . Find the perimeter. _______________
4
11. The area of a triangle is 152 m2, and the height is 16 m. Find the base. _______________
12. The circumference of a circle is 25π mm. Find the radius. _______________
Use the figure for Exercises 13 and 14.
Lucas has a 39-foot-long rope. He uses all the rope to
outline this T-shape in his backyard. All the angles in
the figure are right angles.
13. Find x. _______________
14. Find the area enclosed by the rope. _______________
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Holt Geometry
4. The measures of the vertical angles are
equal.
5. Sample answer: ∠ABM, ∠MBK, and
∠KBC
5. If m∠X + m∠Y = 90° and m∠Z + m∠Y =
90°, then m∠X and m∠Z are both equal
to 90° − m∠Y. So m∠X = m∠Z. Two
angles whose measures are equal are
congruent.
6. C
7. G
8. A
Reading Strategies
1. complementary
6. Possible answer: ∠ADB and ∠ADC
2. vertical
3. supplementary
7.
4. linear or supplementary
5. adjacent
6. complementary
LESSON 1-5
8. 60°
9. 45°
Practice A
10. 72°
Reteach
1. adjacent and form a linear pair
1. side lengths
2. P = 2A + 2w
3. area
4. A =
1
bh
2
2. only adjacent
3. not adjacent
5. 30 yd
6. 54 yd2
4. only adjacent
5. not adjacent
7. 24 cm
8. 24 cm2
6. adjacent and form a linear pair
9. diameter
7. Possible answers: ∠1 and ∠6, ∠2 and ∠5
11. twice
8. Possible answers: ∠1 and ∠2; ∠1 and
∠5; ∠5 and ∠6; ∠6 and ∠2
12.
9. ∠3
10. center
10. complementary
11. neither
12. 34°
13. 124°
14. 68°
15. 158°
16. m∠LMN = 56°; m∠UVW = 34°
13. A = πr 2
Challenge
15. C = 2πr or C = πd
1. 52°14′24″
2. 5°12′
3. 27°37′30″
4. 64°48′
14. around
Practice B
2. 6 ft2
1. 12 ft
5. Sample answer: ∠KLM and ∠MLN
2
ft
5
6. Sample answer: ∠KLH and ∠MLN
3. 2.4 ft or 2
7. 180 − (3x + 2)° or (178 − 3x)°
4. P = 9.6 m; A = 5.76 m2
8. Sample answer: ∠HCK and ∠RCQ
5. P = 2x + 20; A = 7x + 21
6. circumference
Problem Solving
7. C ≈ 44 mi; A ≈ 154 mi2
1. Sample answer: ∠ALB and ∠BLC
8. C ≈ 9.42 cm; A ≈ 7.065 cm2
2. Sample answer: ∠AML and ∠YML
9. C ≈ 2π(x + 1); A ≈ π(x2 + 2x + 1)
3. 45°; they are vertical angles.
10. 2 in.
4. 45°; the angles are supplementary.
11. 19 m
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A5
Holt Geometry
12. 12.5 mm
14. 42 ft
13. 7.5 ft
Reading Strategies
2
1. Answers will vary. Students should
indicate that the perimeter of the square
is the sum of the lengths of the sides.
Practice C
1. 4 units
2. 2 units
2. Answers will vary. Students should point
out that the perimeter of any object is the
sum of the lengths of all the sides.
3. Area is measured in square units, and
perimeter is measured in linear units.
3. Area = length × width or Area = length of
one side × 4
4. A = 121 ft2; A = 11 ft; w = 11 ft
5. For a given perimeter, a rectangle with
sides of equal length (a square) encloses
the maximum area.
6. about 154 ft2
4. Area = length × width; Area = 2 × 2; Area
= 4 square units
7. about 33 ft2
LESSON 1-6
8. If a rectangle and a circle have the same
perimeter, then the circle has the greater
area.
9. 197.5 in2
Practice A
10. a = 8
Reteach
1. 10 ft; 4 ft2
2
2. 32 mm; 64 mm
1. x-axis; y-axis
2. coordinates
⎛ 1 ⎞
3. ⎜ 1 , 0 ⎟
⎝ 2 ⎠
4. (0, −1)
⎛ 1
⎞
5. ⎜ 1 , − 1⎟
⎝ 2
⎠
6.
7. (−2, 4)
8. (−1, −3)
9. 3 miles
10. 4 miles
3. 28 cm; 49 cm2
4. (24 + 2x) in.; 12x in2
5. (18 + y) ft; 4y ft2
6. 24.2 cm; 27 cm2
7. 69.1 in.; 380.1 in2
8. 47.1 mm; 176.7 mm2
11. 1 mile
9. 56.5 in.; 254.5 in2
Practice B
10. 9.4 cm; 7.1 cm2
11. 81.7 m; 530.9 m2
2
12. 103.7 mm; 855.3 mm
Challenge
1. (3, −3)
⎛ x y −3⎞
2. ⎜ ,
2 ⎟⎠
⎝2
3. (−4, −2)
4.
1. P = 11 cm; A = 8.25 cm2
5.
2. The perimeter will double. The area will
be 4 times greater.
7. AB and BC
4. 249.6 m2
5. 11.2 cm2
6. 1.7 in2
7. 45.1 mm2
8. 6.4 units
10. 13.4 ft
11. 101.8 in.
Practice C
1.
Problem Solving
1. 320 yd
2. 6000 yd2
3. about 401.92 yd2
4. 3000 yd2
5. A
6. 4 2 units
26 units
9. 11.4 units
3. The area will be 9 times greater. k2A
26 units
( x1 − x2 )
(
2
+ ( y1 − y 2 ) =
2
( x2 − x1 )
) (
) + ( y − 2y y
2
+ ( y 2 − y1 )
since x12 − 2 x1x2 + x22 + y12 − 2y1y 2 + y 22
=
6. G
(
x22
− 2 x1x2 +
x12
2
2
1 2
+
y12
)
2
)
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