1. Math 3 Unit 3 Lesson: 1A, Transversals 1B, Triangle Congruence
Know:
Special angles created by parallel lines cut by a transversal.
Methods of proving triangles are congruent.
Be able to:
Determine angle congruency and angle measure in a transversal.
Prove two triangles are congruent using mathematical methods.

2. These are Parallel lines “cut” or intersected by a third line, tranversals .
Add >> to indicate parallel lines

3. Supplementary angles A B C D
Vertical angles E F G H
Corresponding angles
Alt. Interior angles
Alt. Exterior angles

4. Congruent Angles (Same size or angle measure) Supplementary Angles
Not Congruent
Supplementary Angles
Vertical Angles
Corresponding Angles
Alternate Interior Angles
Alternate Exterior Angles

5. Kahoot: Computational
Kahoot: Vocabulary for parallel lines and transversals.
Kahoot: Computational

6. i.e. Their relative angles and sides are equal in measure.
Triangle Congruency
Corresponding Parts of Congruent Triangles are Congruent (CPCTC)
i.e. Their relative angles and sides are equal in measure.

7. Five ways to prove triangles are congruent
Side, Side, Side (SSS)
Side, Angle, Side (SAS)
Angle, Angle, Side (AAS)
Angle, Side, Angle (ASA)

8. The fifth way is only true for right triangles
Hypotenuse, Leg (HL)
It means we have two right-angled triangles with
the same length of hypotenuse and
the same length for one of the other two legs.

9. Kahoot.it: Name the Congruent Triangle Rules
(10 easy questions)
Kahoot.it:Congruent Triangles
(26 medium questions)

10. Why isn’t SSA or ASS a valid proof for triangle congruency?

11. Homework