Successfully reported this slideshow.
Upcoming SlideShare
×

# 8.7 translations and rotations 1

1,294 views

Published on

• Full Name
Comment goes here.

Are you sure you want to Yes No
• Be the first to comment

• Be the first to like this

### 8.7 translations and rotations 1

1. 1. Lesson 8.7 , For use with pages 439-444 How many lines of symmetry does the letter have? 2. 1.
2. 2. Lesson 8.7 , For use with pages 439-444 How many lines of symmetry does the letter have? ANSWER 2 ANSWER 2 2. 1.
3. 3. Translations and Rotations Section 8.7 P. 439 - 443
4. 4. Essential Questions <ul><li>What are the similarities and differences among transformations? </li></ul><ul><li>How are the principles of transformational geometry used in art, architecture and fashion? </li></ul><ul><li>What are the applications for transformations? </li></ul>
5. 5. <ul><li>In this section you will learn how TRANSLATE (slide) and ROTATE (turn) figures in a coordinate plane. </li></ul>
6. 6. <ul><li>A translation is a transformation that moves EACH point of a figure the same distance in the same direction. </li></ul><ul><li>Think of it as “SLIDING” the figure on the coordinate plane. </li></ul><ul><li>The image is congruent to the original figure. </li></ul>
7. 9. Translation <ul><li>Translation : </li></ul><ul><ul><li>A change in the x: moves the figure left or right </li></ul></ul><ul><ul><ul><li>Add: moves right Subtraction: moves left </li></ul></ul></ul><ul><ul><li>A change in the y: moves the figure up or down </li></ul></ul><ul><ul><ul><li>Add: moves up Subtraction moves down </li></ul></ul></ul>
8. 10. <ul><li>A translation may look like this: </li></ul><ul><li>(x, y) (x + 6, y – 3) This means each point is moved 6 units to the right and then 3 units down </li></ul>
9. 11. <ul><li>Describe these translations: </li></ul><ul><li>(x , y) (x -4, y + 3) (x, y) (x , y -2) </li></ul>Left 4, up 3 Down 2
10. 12. GUIDED PRACTICE for Example 1 1. Describe the translation from the blue figure to the red figure. SOLUTION Each point moves 5 units to the left and 4 units down. The translation is ( x , y ) -> ( x – 5, y – 4) .
11. 13. ANSWER R' (–3, 7), S' (1, 7), T' (0, 0) 1. RST has vertices R (–1, 4) , S (3, 4) , and T (2, –3) . Translate the figure. ( x , y ) -> ( x – 2 , y + 3). ∆
12. 14. EXAMPLE 1 Using Coordinate Notation Translate the figure. A (-5,4) B(-2,3) C(-2,0) D(-5,0) SOLUTION Each point moves 6 units to the right and 3 units down. The translation is ( x , y ) -> ( x + 6, y –3)
13. 15. EXAMPLE 1 Using Coordinate Notation Translate the blue figure. A (-5,4) B(-2,3) C(-2,0) D(-5,0) ( x , y ) -> ( x + 6, y –3)
14. 16. Homework <ul><li>Page 442 #4-7, 16AB </li></ul>