1. Parallel Lines and Planes
Parthenon
Athens
Dallas City Hall
I.M. Pei
Havasu Falls
I.M. Pei
Parallel Lines and Planes
Lesson 3.2 Classroom Exercises

2. X marks the spot. Vertical angles are congruent.
Mr. Sabia’s Favorite Theorem
Vertical angles are congruent.
X marks the spot.

3. Lp’s are suppl. Mr. Sabia’s 2nd Favorite Theorem a b
Linear pairs are supplementary.
Lp’s are suppl. a b

4. Mr. Sabia’s Third Favorite Theorem
If 2 lines are //, then the Alternate Interior angles are congruent.

5. If two lines are parallel….
The corresponding angles are congruent.
The alternate interior angles are congruent.
The alternate exterior angles are congruent.
The same-side interior angles are supplementary.
The same-side exterior angles are supplementary.

6. T K 1 L
What do the arrowheads in the diagram tell you? P
L // P

7. 2 State the postulate or theorem that justifies each statement. T K L
If 2 lines are parallel and cut by a transversal,
Then the corresponding angles are congruent.

8. 3 State the postulate or theorem that justifies each statement. T K L
If 2 lines are parallel and cut by a transversal,
Then the alternate interior angles are congruent.

9. 4 State the postulate or theorem that justifies each statement. T K L
If 2 lines are parallel and cut by a transversal,
Then the same-side interior angles are supplementary.

10. 5 State the postulate or theorem that justifies each statement. T K L
If 2 lines are parallel and cut by a transversal,
Then the corresponding angles are congruent.

11. 6 State the postulate or theorem that justifies each statement. T K L
If 2 lines are parallel and cut by a transversal,
Then the alternate interior angles are congruent.

12. 7 State the postulate or theorem that justifies each statement. T K L
Vertical angles are congruent.

13. 8 State the postulate or theorem that justifies each statement. T K L
If a line is perpendicular to on of two parallel lines, then it is perpendicular to the other.

14. 9 State the postulate or theorem that justifies each statement. T K L
If 2 lines are parallel and cut by a transversal,
Then the same-side interior angles are supplementary.

15. 10 State the postulate or theorem that justifies each statement. T K L
1300
500 L
500
1300
1300
If the measure of angle 1 is 130, what are the measures of the other angles?
500 P
1300
500

16. 11 State the postulate or theorem that justifies each statement. T K Lx
180-x L
180-x x x
If the measure of angle 1 is x, what are the measures of the other angles?
180-x P x
180-x

17. 12 x 2x State the postulate or theorem that justifies each statement.K L x 2x
60, AIA P
x + 2x = 180
3x = 180
x = 60

18. 13 State the postulate or theorem that justifies each statement. x T KCA L x
x + 20 P
x + x + 20 = 180
2x + 20 = 180
2x = 160
x = 80

19. C’est fini.
Good day and good luck.