Cha
p
Name:
Date:
ter
Area
Practice 1 Finding the Area of a Rectangle with
Fractional Side Lengths
Find the area of each rectangle.
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Example
A = length × width
=3×3
4 5
= 9 in.2
20
The area of the rectangle is 9 square inches.
20
3
_
in.
4
3
_
in.
5
1.
3
_
m
5
A
1
_
m
2
width
1
2
m2
The area of the rectangle is
2.
square meters.
3
_
ft
4
1
_
ft
8
Lesson 6.1 Finding the Area of a Rectangle with Fractional Side Lengths
215
Find the area of each shaded rectangle.
3.
4
cm
5
4.
3
m
7
2
m
4
216
Chapter 6 Area
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5
cm
6
Name:
5.
Date:
A 1-meter square plot of land is covered by a rectangular patch of grass that
measures 47 meter by 23 meter. What is the area of the patch of grass?
4
m
7
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2
m
3
Lesson 6.1 Finding the Area of a Rectangle with Fractional Side Lengths
217
Find the area of the top of a rectangle bedside table with a length of 34 yard and
width that is 16 yard less than the length.
Find the area of each composite figure.
7.
1 cm
_
5
3 cm
_
5
1 cm
_
5
4 cm
_
5
218
Chapter 6 Area
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6.
Name:
Date:
8.
2
_
m
7
4
_
m
9
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4
_
m
7
9.
1
_
9m
_
1
10 m
_
1
5 m
3
_
5 m
4m
_
5
Lesson 6.1 Finding the Area of a Rectangle with Fractional Side Lengths
219
10.
1
2
2
_
_
_
3 yd 9 yd 9 yd
2
_
7 yd
6
_
7 yd
2
_
7 yd
2
_
7 yd
Find the area of the shaded part.
11.
3
_
5 in.
1
_
in.
5
3
1
_
_
5 in. 5 in.
12.
8
_
9 m
2
_
3 m
220
Chapter 6 Area
5
_
9 m
1
_
6m
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7
_
9 yd
Name:
Date:
Practice 2 Base and Height of a Triangle
Complete to give both the base and the height in each triangle.
Example
C
A
height
Height:
Base:
B
W
1.
BA
AC
A
2.
he
igh
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t
V
T
Y
X
B
C
Z
U
base
Height:
Base:
Base:
Height:
3.
T
4.
D
base
A
C
e
bas
V
E
S
U
W
B
Base:
Base:
Height:
Height:
Lesson 6.2 Base and Height of a Triangle
221
For each triangle, the base is given.
Use a drawing triangle to draw the height.
Label the height.
Example
base
5.
6.
ba
ba
se
se
7.
8.
base
e
bas
9.
10.
ba
se
222
Chapter 6 Area
bas
e
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height
Name:
Date:
Practice 3 Finding the Area of a Triangle
Find the area of each shaded triangle. Show each step and
give your answer using the correct units.
Example
23 cm
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15 cm
1 × 23 × 15
Area of triangle 2
172 1 cm2
2
1.
26 m
17 m
Area of triangle 2.
54 cm
Area of triangle 72 cm
3.
70 ft
Area of triangle 45 ft
32 ft
Lesson 6.3
Finding the Area of a Triangle
223
Find the area of each shaded triangle.
Example
4.
8 cm
9 in.
6 cm
1
×8×6
2
Area 24 cm2
Area 6.
5 cm
in.
28 in.
25
18 in.
5 cm
Area Area 8.
7.
25 in.
4 in.
7 in.
5 in
15 in.
.
6 in.
20 in.
224
Area Area Chapter 6 Area
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5.
12 in.
4 in.
6 cm
10 cm
Name:
1.
Date:
Four students found the area of the shaded triangle.
3 cm
4 cm
cm
4 cm
5
These are their findings.
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Zach: 4 4 16 cm2
1
Preeti: 2 5 4 10 cm2
1
Brian: 2 7 4 14 cm2
1
James: 2 3 4 6 cm2
Explain the mistakes they have made. Then write the correct answer.
Zach:
Preeti:
Brian:
James:
The area of the shaded triangle is:
Chapter 6 Area
225
3.
ABCD is a rectangle and BE EC.
A
4 cm
D
3 cm
B
2 cm
E
2 cm C
What can you say about the areas of triangles BED and ECD?
Explain your answer.
226
Chapter 6 Area
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The area of the shaded triangle is 15 square centimeters.
Explain why the area of the rectangle is 30 square centimeters.
2.
Name:
Date:
Put On Your Thinking Cap!
Challenging Practice
Solve. Show your work.
1.
ABCD is a square of side 10 centimeters and BE EC.
Find the area of the shaded triangle.
10 cm
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B
2.
ABCD is a rectangle 18 centimeters
by 8 centimeters. AE ED and AF FB.
Find the area of the shaded triangle.
A
D
A
C
E
E
D
F
B
8 cm
18 cm
Chapter 6 Area
C
227
4.
ABCD is a rectangle of area 48 square inches.
The length of CD is 3 times the length of DF.
BC 4 inches.
a.
Find the length of DF.
b.
Find the area of the shaded triangle.
A
D
ABCD is a rectangle 12 centimeters by 5 centimeters.
BE 4 centimeters. Find the area of the
A
shaded region, ABED.
E
B
F
12 cm
C
D
5 cm
B 4 cm E
228
Chapter 6 Area
C
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3.
Name:
5.
Date:
The side of square ABCD is 8 centimeters. AE AF 4 centimeters.
Find the area of the shaded triangle, CEF.
A
E
D
B
8 cm
C
4 cm
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F
6.
The perimeter of rectangle ABCD is 256 inches. Its length is
3 times as long as its width. Find the area of triangle ABC.
A
D
B
C
Chapter 6 Area
229
ABCD is a rectangle of area 72 square centimeters.
The length of AD is 3 times the length of AE.
BF 8 centimeters.
A
230
E
D
B
F
a.
Find the width of the rectangle.
b.
Find the area of the shaded region, EBFD.
Chapter 6 Area
C
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7.
Name:
Date:
Put On Your Thinking Cap!
Problem Solving
1.
Look at the pattern of these triangles.
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16 cm
8 cm
4 cm
2 cm
2 cm
4 cm
8 cm
Triangle 1
Triangle 2
Triangle 3
16 cm
Triangle 4
What is the area of Triangle 5 in the pattern?
Which triangle in the pattern will have an area of
32,768 square centimeters?
Chapter 6 Area
231
2.
ABCD is a square with sides of 20 centimeters. AX XB, BY YC, CZ ZD,
AW WD. WY and XZ are straight lines. Find the total area of the
shaded parts.
A
W
Z
X
Y
C
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B
D
232
Chapter 6 Area