1. BELL RINGER
Lines q, r, and s are distinct in a plane. If line q is perpendicular to line r, and line r is perpendicular to s, then which of following is true?
q parallel s
q perpendicular to s
Q and s are skew
Q intersects s
S is a transversal of q and r

2. BELL RINGER cont. Draw a line and label it line q.
Draw a line that is perpendicular to line q and label this line r.
Draw a line s that is perpendicular to r.
What do you see? Remember choices…
q parallel s
q perpendicular to s
Q and s are skew
Q intersects s
S is a transversal of q and r

3. Chapter 3 Parallel and Perpendicular Lines
Lesson 3.2: Use Parallel Lines and Transversals
LEARNING TARGET
Solve problems using the corresponding angles postulate, alternate interior angles theorem, alternate exterior angles theorem and consecutive interior angles theorem.

4. Let’s Investigate! 1 2 3 4 5 6 7 8

5. Postulate 15 Corresponding Angles If two parallel lines
are cut by a transversal
then the pairs of
corresponding angles
are congruent. 1 2 3 4 5 6 7 8

6. Theorem 3.1 Alternate Interior Angles Theorem
If two parallel lines are cut by a
transversal, then the
pairs of alternate
interior angles are
congruent. 1 2 3 4 5 6 7 8

7. Theorem 3.2 Alternate Exterior Angles Theorem
If two parallel lines are cut by a transversal,
then the pairs of alternate exterior angles
are congruent. 1 2 3 4 5 6 7 8

8. Theorem 3.3 Consecutive Interior Angles Theorem
If two parallel lines are cut by a transversal, then
the pairs of consecutive interior angles
are supplementary. 1 2 3 4 5 6 7 8

9. Find angles 1 and 2 for each problem.1. 2.
120, 120
120, 60 3. 4.
140, 140
135, 45

10. Let’s Try!
Find the value of x.
115o 4
(x + 5)o

11. Find x. 1. 2. 40 40 3. 4.
110 33

12. Example 1 – Use properties of parallel lines Find the value of x.

13. Example 2 – Use properties of parallel lines Find the value of x.

14. Example 3 – Use properties of parallel lines
Find the value of x and y.

15. Example 4 – Use properties of parallel lines
Find the value of x and y.

16. Homework
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4-18 even, 22,28