Download Notes Section 4-5

Geometry
Notes Section 4-5
What you’ll learn. . . .
How to use the ASA Postulate to
test for triangle congruence
 How to use the AAS Theorem to
test for triangle congruence

Vocabulary

Included side
The two shortcuts we know. . .

SSS

SAS

There are a few more. . .
 ASA
Postulate-If two angles
and the included side of one
triangle are congruent to the
two angles and the included
side of another triangle, then
the triangles are congruent.
Example #1: Find the missing congruent
parts so that the triangles can be proved
congruent by the ASA Postulate. Then
write the triangle congruence.
a.
b.
c.
d.
Example #2: Write a two-column proof.

Given: PS is the angle bisector of
QPR

Prove: ΔPQS  ΔPRS
Might there be more????
 Today is your lucky day. . .

 Do
you think that if two angles
and a nonincluded side of one
triangle are congruent to the
corresponding two angles and
nonincluded side of a second
triangle, the two triangles
would be congruent??

Yes . . .this is called AAS
Example #3: Find the missing congruent parts
so that the triangles can be proved congruent.
Justify your decision. Then write the triangle
congruence.
Example 4:

.
Write a two-column proof.
Have you learned. . . .
How to use the ASA Postulate to
test for triangle congruence
 How to use the AAS Postulate to
test for triangle congruence


Assignment:


Non-Proof: Worksheet 4-4,4-5
Proof:p.211 (10-18 even, 21-28)