Download Exercises 5-5

5-5
Exercises
KEYWORD: MG7 5-5
KEYWORD: MG7 Parent
GUIDED PRACTICE
1. Vocabulary Describe the process of an indirect proof in your own words.
SEE EXAMPLE
1
p. 332
Write an indirect proof of each statement.
2. A scalene triangle cannot have two congruent angles.
3. An isosceles triangle cannot have a base angle that is a right angle.
SEE EXAMPLE
2
p. 333
4. Write the angles in order
from smallest to largest.
5. Write the sides in order
from shortest to longest.
+
9
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8
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3
Tell whether a triangle can have sides with the given lengths. Explain.
1 , 3_
1, 6
6. 4, 7, 10
7. 2, 9, 12
8. 3_
9. 3, 1.1, 1.7
2 2
10. 3x, 2x - 1, x 2, when x = 5
11. 7c + 6, 10c - 7, 3c 2, when c = 2
SEE EXAMPLE 4
The lengths of two sides of a triangle are given. Find the range of possible lengths
for the third side.
SEE EXAMPLE
p. 334
p. 335
12. 8 mm, 12 mm
SEE EXAMPLE
5
p. 335
13. 16 ft, 16 ft
14. 11.4 cm, 12 cm
15. Design The refrigerator, stove, and sink in
a kitchen are at the vertices of a path called
the work triangle.
a. If the angle at the sink is the largest, which
side of the work triangle will be the longest?
b. The designer wants the longest side of this
triangle to be 9 feet long. Can the lengths of
the other sides be 5 feet and 4 feet? Explain.
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PRACTICE AND PROBLEM SOLVING
Independent Practice
For
See
Exercises Example
16–17
18–19
20–25
26–31
32
1
2
3
4
5
Extra Practice
Skills Practice p. S13
Write an indirect proof of each statement.
16. A scalene triangle cannot have two congruent midsegments.
17. Two supplementary angles cannot both be obtuse angles.
18. Write the angles in order
from smallest to largest.
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19. Write the sides in order
from shortest to longest.
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Application Practice p. S32
/
-
,
Tell whether a triangle can have sides with the given lengths. Explain.
20. 6, 10, 15
21. 14, 18, 32
24. z + 8, 3z + 5, 4z - 11, when z = 6
336
22. 11.9, 5.8, 5.8
23. 103, 41.9, 62.5
25. m + 11, 8m, m 2 + 1, when m = 3
Chapter 5 Properties and Attributes of Triangles
ge07se_c05_0332_0339.indd 336
12/2/05 7:18:04 PM