CHAPTER 4: CONGRUENT TRIANGLES

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

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

6. CLASSWORK/HOMEWORK • CW: Pg. 148, Classroom Exercises 1-4 • HW: Pgs. 148-149, Written Exercises 1-6, 9