Dilations Enlarge Reduce

Dilate the figure by a scale factor of 3 with the origin as the center of dilation. What are the coordinates of the image?

• A'(9,9) B'(18,18) C'(27,9)

• A'(6,6) B'(9,9) C'(12,6)

• A'(0,0) B'(3,3) C'(6,0)

• A'(1,1) B'(2,2) C'(3,1)

What is the scale factor?

• k = 2

• k = 1/2

• k = 4

• k = 1/4

Dilate Point B by a scale factor of 3:

• (12,0)

• (12,12)

• (4,3)

• (0,12)

Click image to enlarge

• A

• B

• C

• D

Triangle ABC will be dilated by a scale factor of 1/2.  What will be the coordinates of C'?

• (-1, -2.5)

• (12, 6)

• (3, -1.5)

• (0, 1.5)

If the scale factor is less than 1, the dilation is...

• an enlargement

• a translation

• a rotation

• a reduction

Triangle ABC has vertices A (-2, 2), B (2, 4) and C (3, -1).  What are the coordinates of A' after a dilation by a scale factor of 2.5?

• (-5, 5)

• (5, -5)

• (5, 10)

• (7.5, -2.5)

Triangle PQR is similar to triangle DEF shown. Which describes the relationship between the corresponding sides of the two triangles?

• 
• 
• 
• 

Did the image enlarge, reduce or none of the above?

• Enlarge

• Reduce

• None of the above

Under a dilation, which scale factor will result in a congruent image?

• -2

• 0

• 1

• ¹/₂