Target

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Target
Lesson 4-4 4.5 Proving ?s Congruent
TARGETS

• Use the SSS, SAS, ASA, AAS Postulates to test for
  triangle congruence.

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SSS Congruence
LESSON 4-4 4-5 Proving Triangles Congruent
Side-Side-Side (SSS) Congruence
3 pairs of corresponding sides are congruent
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SAS Congruence
LESSON 4-4 4-5 Proving Triangles Congruent
Side-Angle-Side (SAS) Congruence
2 pairs of corresponding sides and their
included angles are congruent
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ASA Congruence
LESSON 4-4 4-5 Proving Triangles Congruent
Angle-Side-Angle (ASA) Congruence
2 pairs of corresponding angles and their
included sides are congruent
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AAS Congruence
LESSON 4-4 4-5 Proving Triangles Congruent
Angle-Angle-Side (AAS) Congruence
2 pairs of corresponding angles and their
non-included sides are congruent
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Which Method?
LESSON 4-4 4-5 Proving Triangles Congruent
Which Method?
SSS
AAS
ASA
SAS
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Example 2A
LESSON 4-4 SSS, SAS Congruence
EXAMPLE 2
EXTENDED RESPONSE Triangle DVW has vertices
D(5, 1), V(1, 2), and W(7, 4). Triangle LPM
has vertices L(1, 5), P(2, 1), and M(4,
7).a. Graph both triangles on the same
coordinate plane.b. Use your graph to make a
conjecture as to whether the triangles are
congruent. Explain your reasoning.c. Write a
logical argument that uses coordinate geometry
to support the conjecture you made in part b.
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Example 2B
Solve the Test Itema.
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Example 2C
b. From the graph, it appears that the triangles
have the same shapes, so we conjecture that they
are congruent.
c. Use the Distance Formula to show all
corresponding sides have the same measure.
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Example 2C
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Example 2 ANS
Answer WD ML, DV LP, and VW PM. By
definition of congruent segments, all
corresponding segments are congruent. Therefore,
?WDV ? ?MLP by SSS.
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Example 2A
Determine whether ?ABC ? ?DEF for A(5, 5), B(0,
3), C(4, 1), D(6, 3), E(1, 1), and F(5, 1).
A. yes B. no C. cannot be determined

1. A
2. B
3. C