1. Dilations
Chapter 4-8

2. Dilation – enlarging or reducing a figure

3. Dilation – enlarging or reducing a figure
When you dilate a figure, for example, ABC, it is written as A’B’C’

4. Dilation – enlarging or reducing a figure.
When you dilate a figure, for example, ABC, it is written as A’B’C’.
To dilate any image, you simply multiply each coordinate in the ordered pairs by its scale factor.

5. Example Ordered Pairs: (3, 8), (10, 6), (8, 2) Scale factor: ½
First, plot your ordered pairs.
Next, multiply your ordered pairs by the scale factor.
Last, draw a line through the origin and vertices.

6. Example Ordered Pairs: A (3, 8) B(10, 6) C(8, 2) Scale factor: ½
H (2, 1)
I (1, 4)
J (5, 3)
Scale factor: 2
L (0, 0)
M (1, 2)
N (4, 3)
Scale factor: 3

7. Example Now you try! Ordered Pairs: A (3, 6) B(6, 12) C(9, 3)
Scale factor: 1/3
Ordered Pairs:
H (2, 1)
I (2, 3)
J (3, 3)
Scale factor: 3

8. Find and classify a scale factor
If segment V’W’ is a dilation of VW, what is the scale factor?
Write a ratio of the x- or y-coordinate of the vertex of the dilation to the x- or y-coordinate or the other vertex.

9. Use a scale factor
A doctor uses medication to dilate your eyes. The medicine dilates at a scale factor of 5/3.
Before Dilation
5mm