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Daily Homework Quiz For use after Lesson 8.7 2. Where have you seen a translation today?   1.     RST  has vertices  R (–1, 4) ,  S (3, 4) , and  T (2, –3) . Find the vertices of its image after the translation  ( x ,  y )  ->  ( x   – 4 ,  y   + 5). ∆
Daily Homework Quiz For use after Lesson 8.7 2. Where have you seen a translation today?   1.     RST  has vertices  R (–1, 4) ,  S (3, 4) , and  T (2, –3) . Find the vertices of its image after the translation  ( x ,  y )  ->  ( x   – 4 ,  y   + 5). ∆ ANSWER R' (–5, 9),  S' (–1, 9),  T' (–2, 2)
Translations and Rotations Section 8.7 P. 439 - 443
Essential Questions What are the similarities and differences among transformations? How are the principles of transformational geometry used in art, architecture and fashion? What are the applications for transformations?
A rotation is a transformation that “TURNS” each point of a figure the same number of degrees around a common point.  For our lessons, that point will be the origin (0,0).  Rotations may be clockwise or counterclockwise.
A  rotation  is a transformation that “TURNS” each point of a figure the same number of degrees around a common point.  For our lessons, that point will be the origin (0,0).  Rotations may be clockwise or counterclockwise.
 
 
 
Rotation : 90 degrees clockwise switch the coordinates around, and Y will become the opposite sign of the original point. (y, -x) 90 degrees counterclockwise switch the coordinates around, and X will become the opposite sign. (-y, x) 180 degrees  “ opposite” coordinates for both x and y. (-x, -y)
Try this on graph paper! A  90 degrees clockwise rotation   will switch the coordinates around, and Y will become the opposite sign of the original point. Example P (6,2)  P’  (2,- 6) Q (-3,4)  Q’  (  ,  ) W(4,0)  W’  (  ,  )
Graph  A (1, 1), B (3, 1), C (3, 3),  and  D (1, 4) . Find its image after a  90°   clockwise rotation. Switch the coordinates around, and Y will become the opposite sign of the original point. (y, -x) A’ (1,-1) B’ (1, -3) C’ (3, -3) D’ (4, -1)
GUIDED PRACTICE for Example 2 and 3  Graph  A (1, 1), B (3, 1), C (3, 3),  and  D (1, 4) . Find its image after the given rotation. A’ (1,-1) B’ (1, -3) C’ (3, -3) D’ (4, -1) RULE: Switch the coordinates around, and Y will become the opposite sign of the original point. (y, -x) 2.  90   clockwise ANSWER
Try these on graph paper 90 degrees counterclockwise rotation will switch the coordinates around, and X will become the opposite sign. Example:  P (5, 3)  P’ (-3, 5) Q (-4,-2)  Q’  (2, -4) W  (-7, 8)  W’ (  ,  )
Graph  A (1, 1), B (3, 1), C (3, 3),  and  D (1, 4) . Find its image after a  90°   counterclockwise rotation. Switch the coordinates around, and X will become the opposite sign.  (-y, x) A’ (-1,1) B’ (-1, 3) C’ (-3, 3) D’ (-4, 1)
GUIDED PRACTICE for Example 2 and 3  Graph  A (1, 1), B (3, 1), C (3, 3),  and  D (1, 4) . Find its image after the given rotation. A’ (-1,1) B’ (-1, 3) C’ (-3, 3) D’ (-4, 1) RULE: Switch the coordinates around, and X will become the opposite sign.  (-y, x) 3.  90   counterclockwise ANSWER
180 degree rotations will create “opposite” coordinates for both x and y. Example:  P (4, 1)  P’  (-4, -1) Q(-3, 5)  Q’  (3, -5) W (2, -7)  W’ (  ,  ) 180 degrees can be either clockwise or counterclockwise, the result is the SAME!
GUIDED PRACTICE for Example 2 and 3  Graph  A (1, 1), B (3, 1), C (3, 3),  and  D (1, 4) . Find its image after a  180°  rotation. “ opposite” coordinates for both x and y. (-x, -y) A’ (-1,-1) B’ (-3, -1) C’ (-3, -3) D’ (-1, -4)
GUIDED PRACTICE for Example 2 and 3  Graph  A (1, 1), B (3, 1), C (3, 3),  and  D (1, 4) . Find its image after the given rotation. A’ (-1,-1) B’ (-3, -1) C’ (-3, -3) D’ (-1, -4) RULE: “opposite” coordinates for both x and y. (-x, -y) 4.  180 ANSWER
Homework Page 441 #1-3, 9, 11, 12