4.4 Using Congruent Triangles CPCTC 2010 November 01, 2010
4.1 ­ 4.3 Quick Review:
1. Find a partner.
2. Take out one piece of paper to share.
3. Divide the paper into four even boxes.
4. Draw and label an example for each scenario below.
5. Trade with another group to check each others answers.
SSS
In each box, draw and label a pair of triangles that could be proven congruent ASA
by the given theorem.
SAS
AAS
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4.4 Using Congruent Triangles CPCTC 2010 November 01, 2010
4.4 Using Congruent Triangles: CPCTC
Objective: Use triangle congruence and CPCTC to prove that parts of two triangles are congruent.
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4.4 Using Congruent Triangles CPCTC 2010 November 01, 2010
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4.4 Using Congruent Triangles CPCTC 2010 November 01, 2010
Review: You can use three parts of triangles to show that triangles are congruent with SSS, SAS, ASA, and AAS.
Once you know triangles are congruent, you can make conclusions about the remaining parts because, by definition, corresponding parts of congruent triangles are congruent.
CPCTC
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4.4 Using Congruent Triangles CPCTC 2010 Statements
November 01, 2010
Reasons
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4.4 Using Congruent Triangles CPCTC 2010 November 01, 2010
Example:
Statements
Reasons
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4.4 Using Congruent Triangles CPCTC 2010 November 01, 2010
Proof
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4.4 Using Congruent Triangles CPCTC 2010 November 01, 2010
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4.4 Using Congruent Triangles CPCTC 2010 November 01, 2010
About how wide was the river if the officer stepped off 20 paces and each pace was about 2 1/2 feet long?
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4.4 Using Congruent Triangles CPCTC 2010 November 01, 2010
Homework: page 222
(1 ­ 8, 14, 26, 27)
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