Lesson 2.7 Objective: To complete dilations on a coordinate plane. Essential question: How do you enlarge or reduce a figure on a coordinate plane. Vocabulary: Dilation: is an image produced by enlarging or reducing a figure. A dilation is formed by multiplying all coordinates by a scale factor. Dilations: Non Rigid Similar figures Translations: Rotations: Rigid Congruent figures Reflections:

Example: graph the line segment with endpoints (1,2) and (3,-2) then graph the image after a dilation of 2 A’ (2,4) and (6, -4) New Image Multiply all coordinates by 2 for the coordinates of the new image A B B’ LEFT COLUMN QUESTION? What is the difference between rigid and non-rigid transformations? ANSWER: Rigid keep their size and shape. Non rigid keep shape but size changes.

Multiply all coordinates by 2 Example: Graph the triangle with vertices (-1,-1), (1,3) and (3,1) then graph its image after a dilation of 2. Multiply all coordinates by 2 (-2,-2) (2,6) and (6,2)

The Green square is a dilation of the Red square The Green square is a dilation of the Red square. What is the scale factor? 30 Dilation ‘ Original     24 Enlargement Now Lets say the red square is a dilation of the green square. Scale factor? Enlargements have a scale factor greater than 1. Reductions have a scale factor less than 1     Reduction