1. Do Now   Describe the translations in words. 1. 1. (x, y)  (x – 5, y + 3) 2. 2. (x, y)  (x + 2, y - 1) 3. 3. (x, y)  (x + 0, y + 2)

2. Do Now cont’d Plot the points, then find the coordinates of the image after the given translation. 4. A(2, -2) B(4, 2) C(7, -1) (x, y)  (x – 6, y + 4)

3. Do Now cont’d Plot the points, then find the coordinates of the image after the given translation. 5. D(-4, 1) E(-1, 2) F(-1, 0) G(-3, -1) (x, y)  (x + 2, y + 3)

4. Section 12.5 Perform Reflections Objective: use reflections and symmetry Homework: 12.5 Worksheet

5. Vocabulary  Reflection: transformation that uses a line like a mirror to reflect an image (flip an image over a line)  Line of reflection: the line that acts as a mirror

6. Identify Reflections

7. Reflection in the x axis Triangle DEF is the image of triangle ABC after a reflection in the x axis. Point A is 2 spaces away from the x axis, so Point D is 2 spaces away from the axis. A(-7, 2) B(-3, 2) C(-3, 4) D(-7, -2) E(-3, -2) F(-3, -4) (x, y) → (x, -y) Rule for reflection in the x axis: (x, y) → (x, -y)

8. Reflection in the x axis Graph triangle ABC with vertices A(4, 2) B(5, 6) C(7, 3) Graph the image of triangle ABC after a reflection in the x-axis and list the coordinates of the image.

9. Reflection in the y axis Graph segment GE with vertices G(-3, 4) E(2, -1) Graph the image of segment GE after a reflection in the y-axis and list the coordinates of the image. Rule for reflection in the y axis: (x, y) → (-x, y)

10. Examples

11. Line Symmetry  Line of symmetry - line that divides a figure into two equal parts Example: How many lines can you draw through the heart to get equal parts?

12. Line symmetry  Determine the number of lines of symmetry for the figure