9.1, 9.2, & 9.3: Transformations -Translations, Reflections, & Rotations Translations Translation: a “slide” that moves a point a certain distance in a certain direction ( x, y ) ( x a , y b ) Ex1) Find the image of the point B(3, -4) after being translated left 5 and up 7. Translations Ex2) Given the transformation below, describe the translation. X (2,1) X ' (0,4) Ex3) Write a rule to describe the translation PQRS P’Q’R’S’ Reflections Reflection: a “flip” across a specified line Ex4) Find the image of L(-2, 5) after being reflected across the y-axis. Reflections Ex5) Given the transformation below, what line is the point reflected across? Y (3,3) Y ' (5,3) Ex6) Given the points R(-2,-1), A(1,-3), D(-2,-3), draw ΔRAD and its reflection image across the line y = -x + 2. Rotations Rotation: a “turn” of a certain angle about a point called the center of rotation *Unless stated otherwise, rotations are counterclockwise Ex7) Find the image of P(-2,-2) after being rotated 180° about the origin. Rotations Ex8) Find the image of Z(1,-4) after being rotated 270° about the origin. Ex9) Given the points X(0,-1), Y(1,2), Z(4,1), draw ΔXYZ and its rotation of 90° about the origin. Transformations Ex 10) Use P(-5,3) as the preimage for each of the following transformations: Q) Translation: 10 ( x, y ) ( x 4, y 1) 8 6 4 P R) Reflection over: 2 -10 -8 -6 -4 -2 2 4 6 8 10 y 2 -2 -4 -6 -8 -10 S) Rotation of 270° about the origin Transformations Ex11) Find the image of point X(-1, 5) after being translated 4 to the right, reflected across x = 0, and then rotated 180° about the origin. Transformations Ex12) What type of transformation is represented by each figure? b) c) a) HW: p.473 #9-14, 22, 28 p.480 #1-13 odd p.487 #31, 34 (only about the origin)