Dilation in Math

What are the coordinates of the new point P' after dilating point P with a scale factor of K?

• Multiply the scale factor by the X-coordinate

• Multiply the scale factor by the Y-coordinate

• Multiply the scale factor by both the X and Y coordinates

• Divide the scale factor by both the X and Y coordinates

What is the scale factor for a dilation that shrinks the image to one-third its size?

• 1

• 2

• 1/2

• 1/3

What are the coordinates of the new point H' after dilating point H with a scale factor of 1/3?

• -3, 1

• -9, 3

• 3, 1

• 9, 3

What is the result of a dilation when the scale factor is greater than 1?

• The image is stretched to a larger size

• The image is shrunk to a smaller size

• The image is rotated

• The image is reflected

What is the result of a dilation when the scale factor is less than 1?

• The image is stretched to a larger size

• The image is shrunk to a smaller size

• The image is rotated

• The image is reflected

What does a scale factor of 1 represent?

• No change in the image

• A stretch of the image

• A shrink of the image

• A change in shape

What happens to the image when the scale factor is less than 1?

• It is stretched to a larger size

• It is shrunk to a smaller size

• It is rotated

• It is reflected

What is the restriction on stretching out a figure to a larger size?

• There is no restriction

• The scale factor must be greater than 1

• The scale factor must be less than 1

• The scale factor must be equal to 1

What is the scale factor that you must use to map FROG to F'R'O'G'?

Answer explanation

FROG is the larger figure and the preimage. F'R'O'G' is the smaller figure and the new image. This means the figure was dilated by a value less than 1 in order to get smaller.

The side lengths on F'R'O'G' are all half as long as those of FROG. This means FROG must have been dilated by

$\frac{1}{2}$ (or 0.5)

What would be the coordinates of the new image after the following sequence of transformations is applied to Point B(3, 2):

• B''(9, -1)

• B''(9, 6)

• B''(9, 3)

• B''(6, 6)

• B''(6, 3)

Answer explanation

B(3, 2):

1. Dilate by a scale factor of 3 from the origin (multiply the coordinates by 3) B'(9,6)

2. Translate 3 units down (subtract 3 from the y-coordinate) B''(9,3)