4.4 Congruent Triangles.notebook
In your Foldable:
Congruent Triangles
(order matters)
November 02, 2016
∆NLM ≅ ∆RPQ
N R
L
P
M Q
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4.4 Congruent Triangles.notebook
November 02, 2016
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4.4 Congruent Triangles.notebook
November 02, 2016
What we will learn today:
• Use properties of congruent
triangles.
• Prove triangles congruent by using
the definition of congruence.
Geometric figures are congruent if they are the
same size and shape.
Corresponding angles and corresponding sides are
in the same position in polygons with an equal
number of sides.
Two polygons are congruent polygons iff their
corresponding sides are congruent. Thus
triangles that are the same size and shape are
congruent.
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4.4 Congruent Triangles.notebook
November 02, 2016
To name a polygon, write the vertices in consecutive
order.
In a congruence statement, the order of the vertices
indicates the corresponding parts.
Example 1: Naming Congruent Corresponding Parts
Identify all pairs of corresponding congruent parts.
(a) Given: ∆PQR ≅ ∆STW
(b) If polygon LMNP ≅ polygon EFGH, identify all
pairs of corresponding congruent parts.
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4.4 Congruent Triangles.notebook
November 02, 2016
Example 2: Using Corresponding Parts of
Congruent Triangles
(a) Given: ∆ABC ≅ ∆DBC find the value of x.
(b) Given: ∆ABC ≅ ∆DBC find m∠DBC.
(c) Given: ∆ABC ≅ ∆DEF, find the value of x.
(d) Given: ∆ABC ≅ ∆DEF, find m∠F.
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4.4 Congruent Triangles.notebook
November 02, 2016
Example 3a: Proving Triangles Congruent
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4.4 Congruent Triangles.notebook
November 02, 2016
Example 3b: Proving Triangles Congruent
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