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Identify the overlapping triangles. . Parts of sides DG and EG are shared by DFG and EHG . . These parts are HG and FG , respectively. Using Corresponding Parts of Congruent Triangles. LESSON 4-7. Additional Examples.
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Identify the overlapping triangles. Parts of sides DG and EG are shared by DFG and EHG. These parts are HG and FG, respectively. Using Corresponding Parts of Congruent Triangles LESSON 4-7 Additional Examples Name the parts of their sides that DFG and EHG share. Quick Check
Label point M where ZX intersects WY, as shown in the diagram. ZWYX by CPCTC if ZWMYXM. Look at MWX. MWMX by the Converse of the Isosceles Triangle Theorem. Look again at ZWMand YXM. ZMWYMX because vertical angles are congruent, MWMX, and by subtraction ZWMYXM, soZWMYXM by ASA. Using Corresponding Parts of Congruent Triangles LESSON 4-7 Additional Examples Write a Plan for Proof that does not use overlapping triangles. Given: ZXWYWX, ZWXYXW Prove: ZWYX You can prove these triangles congruent using ASA as follows: Quick Check
Plan:XPW YPZ by AAS if WXZZYW. These angles are congruent by CPCTC if XWZ YZW. These triangles are congruent by SAS. Proof: You are given XWYZ. Because XWZ and YZW are right angles,XWZ YZW. WZZW, by the Reflexive Property of Congruence. Therefore, XWZYZW by SAS. WXZZYW by CPCTC, andXPWYPZ because vertical angles are congruent. Therefore, XPWYPZ by AAS. Using Corresponding Parts of Congruent Triangles LESSON 4-7 Additional Examples Write a paragraph proof. Given: XWYZ, XWZ and YZW are right angles. Prove: XPWYPZ Quick Check
1. BCE DCA 1. Reflexive Property of Congruence 2. CACE, BADE 2. Given 7. CBCD 7. Definition of congruence 8. CBECDA 8. SAS 9. CBE CDA 9. CPCTC Using Corresponding Parts of Congruent Triangles LESSON 4-7 Additional Examples Given: CA CE, BA DE Write a two-column proof to show that CBE CDA. Plan: CBE CDA by CPCTC if CBECDA. This congruence holds by SAS if CBCD. Statements Reasons Proof: 3. CA = CE, BA = DE 3. Congruent sides have equal measure. 4. CA – BA = CE – DE 4. Subtraction Property of Equality 5. CA – BA = CB, 5. Segment Addition PostulateCE – DE = CD 6. CB = CD 6. Substitution Quick Check