CHAPTER
Chapter Review
9 9-1 Developing Formulas for Triangles and Quadrilaterals Find each measurement. 1. the area of the rectangle
2. the area of the parallelogram 6.2 in.
x–5 2x + 3
4.2 in. 9.8 in.
2x 2 7x 15
41.16 in.2
3. the value of x when A 240 ft 2
4. the height of the trapezoid with A 110.5 m2 14 m
15 ft
h
x 20 m
8 ft
6.5 m
3. The geoboard shows a rectangle, a triangle and a trapezoid. Find the perimeter and area of each. rectangle: P 20; A 21 triangle: P 12; A 8 trapezoid: P 9 42 17 18.8; A 18
9-2 Developing Formulas for Circles and Regular Polygons Find each measurement. 6. the circumference of C in terms of
7. the area of O in terms of
12
C
O
6 in.
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9 x 2 4
3x in.
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Geometry
CHAPTER 9 REVIEW CONTINUED
Find the area of eac h regular polygon. Round to the nearest tenth. 8. a regular pentagon with perimeter 75 m
9. a regular octagon with apothem 8 in. 211.2 in.2
387.1 m2
9-3 Composite Figures Find the shaded area. Round to the nearest tenth, if necessary. 10.
11.
28 cm
8 mm 10 mm
12 mm
18 cm
10 mm
120 mm2
631.2 cm2
12. A map of an irregularly shaped pond is shown on the grid. The grid has squares with lengths of 1 yd. A clarifying chemical is added to the pond, based on the area of the pond. The chemical costs $13.88 per square yard. Find the total cost of applying the clarifying chemical to the pond. $291.48
Copyright © by Holt, Rinehart and Winston. All rights reserved.
202
Geometry
CHAPTER 9 REVIEW CONTINUED
9-4 Perimeter and Area in the Coordinate Plane Draw and classify the polygon with the given ver tices. Find the perimeter and area of the polygon. 13. A(2, 1), B(5, 1), C(2, 4)
14. D(2, 3), E(6, 3), F(6, 3), G(2, 3)
y
y 8
4
A 2 –4 –2
D4
B 2
4
x
–8 –4
–2
G–4
C –4
–8
right triangle; P 12 74 20.6; A 17.5
E 4
8
x
F
rectangle; P 28; A 48
Find the area of eac h polygon with the given ver tices. 15. H(3, 3), I(3, 3), J(5, 2), K(–4, 2) A 37.5
16. L(3, 2), M(4, 2), N(7, 1), P(0, 1) A 21
9-5 Effects of Changing Dimensions Proportionally Describe the effect of each change on the perimeter and area of the given figure. 17. The length of each diagonal of the rhombus is halved.
8 cm 15 cm
The perimeter is halved. The area is quar tered.
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203
Geometry
CHAPTER 9 REVIEW CONTINUED
18. The base and height of the parallelogram are both tripled. The perimeter is tripled. The area is increased by a factor of 9.
8 in.
10 in.
20 in.
19. The base and height of a right triangle with base 7 mm and height 24 mm are doubled. The perimeter is doubled. The area is increased by a factor of 4. 20. The radius of a circle with radius 5 cm is doubled. The circumference is doubled. The area is increased by a factor of 4. 21. A square has vertices (0, 1), (0, 3), (4, 3) and (4, 1). If the area of the square is doubled, what happens to the side length? The side length is increased b y a factor of 2 . 22. A pizza shop specializes in two sizes of pizza, the regular and the extra large. The regular has a 16-in diameter and requires 4 cups of dough. The diameter of the extra large pizza is 20 inches. About how much dough is needed to make an extra large pizza? 1
64 cups of dough
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204
Geometry
CHAPTER 9 REVIEW CONTINUED
9-6 Geometric Probability Use the spinner to find the pr obability of each event. 23. the pointer landing on red
green red 30°
11 36
110° 130°
24. the pointer landing on blue or green
blue
4 9
90°
yellow
25. the pointer not landing on yellow 3 4
26. the pointer on yellow, red, or blue 11 12
27. A bus makes a stop at an intersection five times each hour. The stops last three minutes each, find the probability that a bus will be waiting if you randomly walk up to the bus stop. 15 1 25% 60 4
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205
Geometry
