Download Practice C Classifying Triangles 9-6

Name
LESSON
Date
Class
Practice C
9-6 Classifying Triangles
Classify each triangle according to its sides and angles.
1.
2.
3.
Classify each triangle according to the lengths of its sides.
4. 9.9 cm, 9 cm, 0.99 cm
5. 40 ft, 4 ft, 40 ft
6. 22 ft, 22 ft, 21 ft
7. 2.3 in., 2.3 in., 2.3 in.
8. 5.6 m, 5.06 m, 5.16 m
9. 19 cm, 18 cm, 19 cm
Classify each triangle according to the measures of its angles.
10. 25°, 75°, 80°
11. 178°, 1°, 1°
12. 90°, 40°, 50°
13. 45°, 40°, 95°
14. 23°, 90°, 67°
15. 55°, 60°, 65°
Identify the different types of triangles in each figure and
determine how many of each there are.
16.
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
17.
51
Holt Mathematics
Practice B
9-6 Classifying Triangles
Practice A
9-6 Classifying Triangles
LESSON
LESSON
Classify each triangle according to its sides and angles.
Classify each triangle according to its sides and angles.
Choose the terms needed from the box.
e
cele
s
e
isosceles right
isosceles acute
4.
1.
2.
equilateral
4.
6.
scalene right
scalene acute
5.
7.
scalene acute
5.
3.
isosceles obtuse
scalene obtuse
3.
ral
s
righ
t
t
ob
sce
le
isos
e
us
2.
ate
en
ob
les
al
len
ne
le
sca
1.
sc
sca
tuse
sce
iso
ac
use equi
obt
l
iso
ac
ut
e
eles
ute right
ute
ac
ne
ale
sc
isosc
7.
6.
isosceles right
scalene acute
9.
9.
isosceles obtuse
scalene acute
scalene right
Identify the different types of triangles in each figure and
determine how many of each there are.
10.
scalene right
scalene obtuse
8.
isosceles acute
8.
equilateral
11.
isosceles obtuse
Describe the different kinds of triangles in each figure by their
sides and angles and determine how many of each there are.
10.
11.
1 scalene right ,
2 isosceles right,
1 isosceles acute,
4 equilateral
1 scalene obtuse
4 scalene obtuse
1 scalene acute
2 isosceles acute,
2 isosceles obtuse
4 scalene right
49
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Holt Mathematics
LESSON
Classify each triangle according to its sides and angles.
2.
scalene obtuse
All triangles have at least two acute angles.
If the third angle is acute,
the triangle is an acute
triangle.
3.
isosceles acute
scalene right
scalene
7. 2.3 in., 2.3 in., 2.3 in.
equilateral
5. 40 ft, 4 ft, 40 ft
isosceles
8. 5.6 m, 5.06 m, 5.16 m
4 in.
11. 178°, 1°, 1°
5 in.
13. 45°, 40°, 95°
obtuse
14. 23°, 90°, 67°
1. Each of the 3 angles is less than 90°, so the
right
2m
2m
acute
triangle.
5 ft 60° 5 ft
60° 60°
5 ft
2. The triangle has 3 sides that have the same
15. 55°, 60°, 65°
right
2m
Use the figure to complete the statements.
12. 90°, 40°, 50°
obtuse
7 cm
3 cm
isosceles
triangle is an
acute
A triangle is equilateral
if all three sides are
the same length.
6 in.
Classify each triangle according to the measures of its angles.
10. 25°, 75°, 80°
A triangle is isosceles
if two sides are the same
length.
7 cm
9. 19 cm, 18 cm, 19 cm
scalene
If the third angle is
obtuse, the triangle is
an obtuse triangle.
obtuse
A triangle is scalene if
each side is a different
length.
6. 22 ft, 22 ft, 21 ft
isosceles
If the third angle is right,
the triangle is a right
triangle.
acute
Classify each triangle according to the lengths of its sides.
4. 9.9 cm, 9 cm, 0.99 cm
Holt Mathematics
Review for Mastery
9-6 Classifying Triangles
Practice C
9-6 Classifying Triangles
LESSON
1.
50
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
equilateral
length, so it is an
triangle.
Use the figure to complete the statements.
acute
3. The triangle has a 90° angle, so it is a
right
Identify the different types of triangles in each figure and
determine how many of each there are.
16.
10 cm
triangle.
90° 45°
10 cm
4. The triangle has 2 sides that have the same
17.
length, so it is an
isosceles
45° 14 cm
triangle.
Use the figure to complete the statements.
1 isosceles acute,
2 scalene right,
2 scalene obtuse
3 equilateral
5. The triangle has an angle that measures more
than 90°, so it is an
obtuse
6. Each side of the triangle has a different length,
so it is a
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
51
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
Holt Mathematics
scalene
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
107
14 in.
30°
10 in.
triangle.
40° 110°
8 in.
triangle.
52
Holt Mathematics
Holt Mathematics