1. Congruent Triangles Chapter 4-3

2. Standard 5.0Students prove that triangles are congruentor similar, and they are able to use the concept of corresponding parts of congruent triangles. Lesson 3 CA

3. Congruent Triangles • Two triangles are congruent if all of their corresponding sides and corresponding angles are congruent.

4. Y B X C A Z AB YX BC XZ AC YZ Congruent Triangles ABC  YXZ Order is important!!! Congruent Angles Congruent Sides A  Y B  X C  Z

5. Corresponding Congruent Parts B. ARCHITECTURE A tower's roof is composed of congruent triangles all converging toward a point at the top. Name the congruent triangles. Answer:ΔHIJ  ΔKIL Lesson 3 Ex1

6. A. ARCHITECTURE A tower's roof is composed of congruent triangles all converging toward a point at the top. Name the corresponding congruent angles and sides of Corresponding Congruent Parts Lesson 3 Ex1

7. A. B. C. D. A. The support beams on the fence form congruent triangles. Which of the following congruence statements directly matches corresponding angles or sides ΔABC and ΔDEF? Lesson 3 CYP1

8. B. The support beams on the fence form congruent triangles. Which statement correctly names the congruent triangles? A.ΔACB  ΔEDF B.ΔCBA  ΔFED C.ΔBCA  ΔDFE D.ΔBAC  ΔEFD Lesson 3 CYP1

9. B C A E D F Third Angles Theorem • If two angles of one triangle are congruent to two angles of another triangle, then the third angles are also congruent. If A  D and B  E, then C  F.

10.  Congruence Properties • Reflexive Property of   Every triangle is congruent to itself • Symmetric Property of   If ABC  DEF, then DEF  ABC. • Transitive Property of   If ABC  DEF, and DEF  JKL, then ABC  JKL.

11. A. COORDINATE GEOMETRY The vertices of are R(─3, 0), S(0, 5), and T(1, 1). The vertices of ST are R(3, 0), S(0, ─5), and T(─1, ─1). Transformations in the Coordinate Plane Use the Distance Formula to find the length of each side of the triangles. Lesson 3 Ex2

12. Transformations in the Coordinate Plane Lesson 3 Ex2

13. Transformations in the Coordinate Plane Lesson 3 Ex2

14. Homework Chapter 4-3 • Pg 220: 6-9 10-13 use the distance formula to show that the sides are congruent 20, 25-28, 39-41