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5. 5-6 Congruence Warm Up Problem of the Day Lesson Presentation Pre-Algebra

6. Learning Goal Assignment Learn to use properties of congruent figures to solve problems.

7. Vocabulary correspondence

8. A correspondence is a way of matching up two sets of objects. If two polygons are congruent, all of their corresponding sides and angles are congruent. In a congruence statement, the vertices in the second polygon are written in order of correspondence with the first polygon.

9. Additional Example 1A: Writing Congruent Statements Write a congruence statement for the pair of polygons. The first triangle can be named triangle ABC. To complete the congruence statement, the vertices in the second triangle have to be written in order of the correspondence. A@Q, so A corresponds to Q. B@R, so B corresponds to R. C@P, so C corresponds to P. The congruence statement is triangle ABC@ triangle QRP.

10. Try This: Example 1A Write a congruence statement for the pair of polygons. The first trapezoid can be named trapezoid ABCD. To complete the congruence statement, the vertices in the second trapezoid have to be written in order of the correspondence. A B | 60° 60° || |||| 120° 120° ||| D C A@S, so A corresponds to S. Q R ||| 120° 120° B@T, so B corresponds to T. || |||| C@Q, so C corresponds to Q. 60° 60° | D@R, so D corresponds to R. T S The congruence statement is trapezoid ABCD@ trapezoid STQR.

11. Pre-Algebra HW Page 741 #1-10

12. Additional Example 1B: Writing Congruent Statements Write a congruence statement for the pair of polygons. The vertices in the first pentagon are written in order around the pentagon starting at any vertex. D@M, so D corresponds to M. E@N, so E corresponds to N. F@O, so F corresponds to O. G@P, so G corresponds to P. H@Q, so H corresponds to Q. The congruence statement is pentagon DEFGH@ pentagon MNOPQ.

13. Try This: Example 1B Write a congruence statement for the pair of polygons. The vertices in the first hexagon are written in order around the hexagon starting at any vertex. 110° A B A@M, so A corresponds to M. 110° 140° 140° F B@N, so B corresponds to N. C 110° C@O, so C corresponds to O. E 110° D N D@P, so D corresponds to P. 110° O M E@Q, so E corresponds to Q. 140° 110° 110° F@L, so F corresponds to L. P 140° L The congruence statement is hexagon ABCDEF@ hexagon MNOPQL. 110° Q

14. WX @ KL a + 8 = 24 –8 –8 a = 16 Additional Example 2A: Using Congruence Relationships to Find Unknown Values In the figure, quadrilateral VWXY@ quadrilateral JKLM. A. Find a. Subtract 8 from both sides.

15. IH @ RS 3a = 6 3a = 6 3 3 Try This: Example 2A In the figure, quadrilateral JIHK@ quadrilateral QRST. A. Find a. Divide both sides by 3. 3a I H a = 2 6 4b° S R 120° J 30° Q K c + 10° T

16. ML @ YX 6b = 30 6b = 30 6 6 Additional Example 2B: Using Congruence Relationships to Find Unknown Values In the figure, quadrilateral VWXY@ quadrilateral JKLM. B. Find b. Divide both sides by 6. b = 5

17. H @S 4b = 120 4b = 120 4 4 Try This: Example 2B In the figure, quadrilateral JIHK@ quadrilateral QRST. B. Find b. Divide both sides by 4. 3a I H b = 30° 6 4b° S R 120° J 30° Q K c + 10° T

18. J @V 5c = 85 5c = 85 5 5 Additional Example 2C: Using Congruence Relationships to Find Unknown Values In the figure, quadrilateral VWXY@ quadrilateral JKLM. C. Find c. Divide both sides by 5. c = 17

19. K @T c + 10 = 30 c + 10 = 30 –10 –10 Try This: Example 2C In the figure, quadrilateral JIHK@ quadrilateral QRST. C. Find c. Subtract 10 from both sides. 3a I H c = 20° 6 90° 4b° S R 120° 90° J 30° c + 10° Q K T

21. 5-7 Transformations Warm Up Problem of the Day Lesson Presentation Pre-Algebra

22. 5-7 Learning Goal Assignment Learn to transform plane figures using translations, rotations, and reflections.

23. Vocabulary transformation translation rotation center of rotation reflection image

24. When you are on an amusement park ride, you are undergoing a transformation. Ferris wheels and merry-go-rounds are rotations. Free fall rides and water slides are translations. Translations, rotations, and reflectionsare type of transformations.

25. The resulting figure or image, of a translation, rotation or reflection is congruent to the original figure.

26. Additional Example 1A & 1B: Identifying Transformations Identify each as a translation, rotation, reflection, or none of these. B. A. rotation reflection

27. A’ C’ D’ A’ B’ B’ C’ Try This: Example 1A & 1B Identify each as a translation, rotation, reflection, or none of these. A. B. B A A C D C B reflection translation

28. Additional Example 1C & 1D: Identifying Transformations Identify each as a translation, rotation, reflection, or none of these. C. D. none of the these translation

29. Try This: Example 1C & 1D Identify each as a translation, rotation, reflection, or none of these. E’ C. D. A’ F’ D’ A B’ B C’ F C D none of these rotation E

30. A’ B’ C’ Additional Example 2A: Drawing Transformations Draw the image of the triangle after the transformation. A. Translation along AB so that A’ coincides with B A B C

31. B’ A. Translation along DE so that E’ coincides with D C’ F’ A’ D’ E’ Try This: Example 2A Draw the image of the polygon after the transformation. B C A F D E

32. B’ C’ A’ Additional Example 2B: Drawing Transformations Draw the image of the triangle after the transformation. B. Reflection across BC. A B C

33. B. Reflection across CD. B’ C’ A’ F’ D’ E’ Try This: Example 2B Draw the image of the polygon after the transformation. B C A D F E

34. C’ A’ B’ Additional Example 2C: Drawing Transformations Draw the image of the triangle after the transformation. C. 90° clockwise rotation around point B A B C

35. D’ C’ B’ F’ E’ A’ Try This: Example 2C Draw the image of the polygon after the transformation. C. 90° counterclockwise rotation around point C B C A F D E

36. Additional Example 3A: Graphing Transformations Draw the image of a triangle with vertices of (1, 1), (2, –2 ), and (5, 0) after each transformation. A. 180° counterclockwise rotation around (0, 0)

37. Try This: Example 3A Draw the image of a shape with vertices of (1, –2), (3, 2), (7, 3), and (6, –1) after each transformation. A. 180° clockwise rotation around (0, 0) y 2 x –2

38. Additional Example 3B: Graphing Transformations Draw the image of a triangle with vertices of (1, 1), (2, –2 ), and (5, 0) after each transformation. B. Translation 5 units left

39. Try This: Example 3B Draw the image of a shape with vertices of (1, –2), (3, 2), (7, 3), and (6, –1) after each transformation. B. Translation 10 units left y 2 x –2

40. Additional Example 3C: Graphing Transformations Draw the image of a triangle with vertices of (1, 1), (2, –2 ), and (5, 0) after each transformation. C. Reflection across the x-axis

41. Try This: Example 3C Draw the image of a shape with vertices of (1, –2), (3, 2), (7, 3), and (6, –1) after each transformation. C. Reflection across the x-axis y 2 x –2