MSM07G7_RESBK_Ch05_061-068.pe
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Page 62
Name
Date
Class
Practice B
LESSON
5-8 Using Similar Figures
ABC ⬃ DEF in each pair. Find the unknown lengths.
1.
2.
20 ft
A
21 cm
B
D
A 27 cm
35 cm
C
E
36 cm
x
B
E
15 ft
x
18 ft
45 cm
28 ft
F
D
24 ft
F
C
x 60 cm
3.
x 21 ft
4.
B
D
A
E
7.5 m
15 in.
6m
A
3m C
x
8 in.
4m
D 2m F
B
x5m
x
10 in.
6 in.
C
F
9 in.
E
x 12 in.
5. The two rectangular picture frames at
the right are similar. What is the height
of the larger picture frame?
2.8 feet
?
2 ft
3 ft
f
6. A palm tree casts a shadow that is 44
feet long. A 6-foot ladder casts a
shadow that is 16 feet long. Use
Estimate the height of the palm tree.
4 2 fft
4.2
6 ft
6 ft
16.5 feet
16 ft
44 ft
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
62
Holt Mathematics
Puzzles, Twisters & Teasers
5-7 Concentrating on Figures
Reading Strategies
5-7 Understanding Vocabulary
LESSON
LESSON
Pretend this is a game of concentration. The object of the game
is to match cards with similar figures. Each box represents a
card with a figure on it. When you match 2 cards, cross them out.
Rearrange the letters of the unmatched cards to solve the riddle.
Similar means almost the same. If two objects are similar, they have
some things in common.
Similar figures are figures that are nearly the same. Similar figures
have the same shape, but are different sizes.
Similar figures have corresponding sides and corresponding
angles. Corresponding means matching. Each side and angle in a
similar figure has a corresponding side and angle.
These two triangles are similar.
A
R
21
H
60
A
60
C
R
I
20
S
6
A
4
B
F
4
E 3 F
Y
8
Use the figures above to answer each question.
D
1. What angle corresponds to angle B?
W 15
S
9
X
10
15
G
J
27
R
5
12
M
Y
I
6
V
T
V
15
Y
9
Z
5
8
56
56
X
Y
U
8
C
J
X
W
angle E
N
L
2. What angle corresponds to angle A?
angle D
7.5
K
S
6.5
N
M
C
7
3. What side corresponds to side BC?
T
L
G
I
3
7
E
50
50
side EF
M
9
4
U
16
yes
O
4
2m
4m
L
J
3m
K
5m
6m
5
P
5m
4m
T
15
L
3
K
5m
P
S
20
15
Q
N
6
R
G
10
6
M
12
J
no
5.
20
O
O
Are the figures similar? Answer yes or no for each pair.
4.
U 2
50
K
4
6
40
D
10
B
21
50
H
8
G
I
9
I
L
15
O
K
L
What kind of flowers are on your face?
T
59
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
Holt Mathematics
Practice A
5-8 Using Similar Figures
12 ft
5 ft
A 13 ft C
X
S
60
Holt Mathematics
ABC DEF in each pair. Find the unknown lengths.
1.
2.
D
J 6 cm K
x
4 cm
7 cm
L
F
10 ft
26 ft
P
Practice B
5-8 Using Similar Figures
Y
x
I
LESSON
For each pair of similar figures write a proportion containing
the unknown length. Then solve.
B
L
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
LESSON
1.
U
Z
2.
20 ft
A
12 cm
E
A 27 cm
21 cm
35 cm
C
B
E
36 cm
14 cm
12 in.
28 ft
F
x
4.
Y
3.
24 ft
G
18 m
15 m
H
x
12
; x 18 in.
24
16
D
A
E
7.5 m
T
20 in. Z
x 21 ft
4.
B
24 in.
16 in.
D
x
F
x 60 cm
x
14
; x 8 cm
4
7
X
V 15 in. W
15 ft
C
x
10
; x 24 ft
12
5
U
E
18 ft
45 cm
x
Possible answers are given.
3.
B
D
10 m
x
J
S
15 in.
6m
12 m
6m
A
R
3m C
x
8 in.
4m
D 2m F
B
x5m
x
18
; x 9 m
6
12
6 in.
C
F
9 in.
E
x 12 in.
5. The two rectangular picture frames at
the right are similar. What is the height
of the larger picture frame?
5. Kareem and Julio have rectangular
model train layouts that are similar to
each other. Julio’s layout is 4 feet by
7 feet. Kareem’s layout is 6 feet
wide. What is the length of Kareem’s
layout?
x
10 in.
2.8 feet
?
2 ft
3 ft
f
4 2 fft
4.2
7 ft
10.5 feet
6 ft
Kareem
6. A 6-foot-tall adult casts a shadow
that is 15 feet long. Estimate the
height of a child who casts a 10-foot
shadow.
6. A palm tree casts a shadow that is 44
feet long. A 6-foot ladder casts a
shadow that is 16 feet long. Use
Estimate the height of the palm tree.
4 ft
Julio
6 ft
6 ft
16.5 feet
6 ft
15 ft
16 ft
44 ft
10 ft
4 feet
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
61
Copyright © by Holt, Rinehart and Winston.
Holt Mathematics
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
91
62
Holt Mathematics
Holt Mathematics