Dilation
Definition of Dilation
Dilation is a similarity transformation in which a figure is enlarged or reduced using a scale factor ? 0, without altering the center.
More About Dilation
 When the scale factor of a dilation is greater than 1, the dilation is an enlargement.
 When the scale factor of a dilation is less than 1, the dilation is a reduction.
Example of Dilation

In the figure shown, triangle ADE is enlarged to triangle ABC using a scale factor 4. Here, A is the center of dilation.
Video Examples: Dilation
Solved Example on Dilation
Ques: A'B'C'D' is a dilation of ABCD. Find the scale factor if AB = 2 � A'B'.
Choices:
A. 2B. 5
C. 0.5
D. 0.2
Correct Answer: C
Solution:

Step 1: A'B'C'D' is a dilation of ABCD.
Step 2: AB = 2 � A'B' implies A'B' = 0.5 � AB
Step 3: So, the scale factor is 0.5.
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