1. CHAPTER 4: CONGRUENT TRIANGLES
Section 4-6:
Using More than one Pair of Congruent Triangles

2. CONCEPT
In section 4-3, we learned to derive information about corresponding parts of triangles after we had proved them congruent.
In each scenario, we dealt with only 2 triangles.
In section 4-6 we will generally use 4 different triangles in order to derive information.

3. CONCEPT
The method we will use for all problems in this section follow the same pattern:
Identify information to prove the 1st set of 2 triangles congruent.
Derive information from CPCTC to prove the 2nd set of 2 triangles congruent.
Derive identified information from CPCTC of 2nd set triangles.

4. EXAMPLE 1 ≡ 2; 3 ≡ 4 SV ≡ SV ∆USV ≡ ∆WSV UV ≡ WV TV ≡ TV ∆TUV ≡ ∆TWV
Given: ≡ 2;
3 ≡ 4
Prove: TU ≡ TW S 1 3 T V 2 4 W
1 ≡ 2; ≡ 4
SV ≡ SV
∆USV ≡ ∆WSV
UV ≡ WV
TV ≡ TV
∆TUV ≡ ∆TWV
TU ≡ TW
Given
Reflexive
ASA
CPCTC
SAS

5. PRACTICE ∆BOX ≡ ∆DOY 2. BX ≡ DY 3. ∆ABX ≡ ∆CDY 4. AB ≡ CD ASA CPCTC
Supply a reason for each key step of the proof that AB ≡ CD A B Y
∆BOX ≡ ∆DOY
2. BX ≡ DY
3. ∆ABX ≡ ∆CDY
4. AB ≡ CD
ASA
CPCTC
SAS

6. CLASSWORK/HOMEWORK CW: Pg. 148, Classroom Exercises 1-4
HW: Pgs , Written Exercises 1-6, 9