Download M3U3L1 Transversals and Triangle Congruence

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.
These are Parallel lines “cut” or
intersected by a third line, tranversals .
A B
C D
E F
G H
Alt. Interior angles
Supplementary angles
Vertical angles
Corresponding angles
Alt. Exterior angles
Congruent Angles
(Same size or angle measure)
Congruent
Supplementary Angles
Vertical Angles
Corresponding Angles
Alternate Interior Angles
Alternate Exterior Angles
Not
Congruent
Kahoot: Vocabulary for parallel
lines and transversals.
Kahoot: Computational
Triangle Congruency
Corresponding Parts of Congruent Triangles
are Congruent (CPCTC)
i.e. Their relative angles and
sides are equal in measure.
Five ways to prove triangles are congruent
Side, Side, Side (SSS)
Angle, Angle, Side (AAS)
Side, Angle, Side (SAS)
Angle, Side, Angle (ASA)
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.
Kahoot.it: Name the
Congruent Triangle Rules
(10 easy questions)
Kahoot.it:Congruent Triangles
(26 medium questions)
Why isn’t SSA or ASS a valid proof for triangle
congruency?
Homework