1. Dilations!

2. 43210 In addition to level 3.0 and above and beyond what was taught in class, I may:  Make connection with real-world situations  Make connection with other concepts in math  Make connection with other content areas. I understand and use informal arguments to prove congruency and similarity using physical models, transparencies or geometry software.  informally prove similarity of triangles  Use scale factors to create and analyze dilations. I understand congruency and similarity using physical models, transparencies or geometry software.  construct triangles  Calculate dilations with scale factors. With help from the teacher, I have partial success with the unit content. Even with help, I have no success with the unit content. Learning Goal 1 (8.G.A.3 & 4): The student will understand and use informal arguments to prove congruency and similarity using physical models, transparencies or geometry software.

3. What is a dilation? Play video

4. What is a dilation (in math)? A type of transformation that changes size of the image. The image is similar (same shape but different size). Scale Factor: measures how much larger or smaller the image is.

5. Scale Factors A scale factor greater than 1 causes stretching. A scale factor less than 1 causes shrinking. Both are dilations.

6. How to Graph Dilations 1.Graph the given points. 2.Multiply each coordinate by the given scale factor. 3.List the new ordered pairs. 4.Plot the new points.

7. Labsheet 4.1 Dilation with scale factor of 3. Multiply each “x” by 3 and each “y” by 3. Graph the new ordered pairs. PointPQRS Original Coordinates(2, 4) Coordinates after Dilation (2, 2)(5, 2) (4, 4) (6, 12)(6, 6) (15, 6) (12, 12) P’ S’ R’ Q’