Lesson 9-4 for exercise sets. &KDSWHU
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Use the figure at the right for exercises 1–8.
Justify your answers.
In the figure, line || line n, CDis a transversal,
ABline and line n, and m 3 55
.
1.m 2 2.m 4
3.m 5 4.m 6
5.m 7 6.m 8
7.m 9 8.m 10
9.Use the figure below. Solve for x.
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You can use your understanding of parallel lines and the relationships
among angle pairs to find missing angle measures.
In the figure, line || line nand m 1 60
.
m 2 120
1 and 2 are supplementary angles.
m 3 60
1 and 3 are vertical angles.
m 4 120
1 and 4 are supplementary angles.
m 5 60
3 and 5 are alternate interior angles.
m 6 120
2 and 6 are corresponding angles.
m 7 60
1 and 7 are alternate exterior angles.
m 8 120
4 and 8 are corresponding angles.
n
34
21
7 8
65
t
B
C
A
D
n
4
5
6
2
13
910
78 1211
1314
(2x)°
x°
MN
PQ
For exercises 10–12, is the statement true? Write always, sometimes, or never.
10.Alternate exterior angles are corresponding angles.
11.Angles that are adjacent to corresponding angles are congruent.
12.Alternate interior angles are supplementary.
13.Discuss and Write How are interior angles on the same side
of the transversal related? Do exterior angles on the same side
of the transversal have the same relationship? Use the figure
at the top of this page to help explain your answer.
MN PQ