1. Dilation OF A POLYGON

2. A TRANSFORMATION IN WHICH A POLYGON MAINTAINS ITS SHAPE BUT IS ENLARGED OR REDUCED BY A GIVEN FACTOR AROUND A CENTER POINT. AN OBJECT AND ITS DILATION ARE CONSIDERED SIMILAR FIGURES.

3. Image THE DILATION OF AN OBJECT IS CALLED ITS IMAGE. WE HAVE SPECIAL NOTATION FOR THE NEW SHAPE: ABCD BECOMES A’B’C’D’

4. A DILATION USED TO CREATE A LARGER IMAGE IS CALLED AN ENLARGEMENT.

5. A DILATION USED TO CREATE A SMALLER IMAGE IS CALLED A REDUCTION.

6. Scale factor (SF) THE LENGTH OF EACH SIDE OF AN OBJECT IS MULTIPLIED BY A SCALE FACTOR TO FIND THE LENGTH OF THE SIDE OF THE DILATION IMAGE. THE |SF | >1 IF IT IS AN ENLARGEMENT THE |SF| < 1 IF IT IS A REDUCTION

7. Interactive website CHECK OUT THIS WEBSITE TO GET A GREAT VISUAL OF WHAT THE CHANGE IN SCALE FACTOR DOES TO THE ORIGINAL OBJECT: HTTP://WWW.MATHOPENREF.COM/DILATE.HTML

8. Dilate a point IF I HAVE POINT A(3,1) GRAPHED AND I WANT TO DILATE IT BY A SCALE FACTOR OF 2, I SIMPLY MULTIPLY EACH COORIDINATE BY 2: (3*2, 1*2) TO GET MY NEW POINT A’(6,2)

9. Triangle ABC was dilated by a scale factor making it smaller. Can you determine what the scale factor is?

10. If you compare the points, the points changed by a scale factor of -1/2. A(-2, 12) A’(1, -6) B(6, 0) B’(-3, 0) C(-8, 6) C’(4, -3)