Scale Factor and Dilations

Front

What is a scale factor?

Back

The scale factor is the ratio of a length of the image to the corresponding length on the original figure.

Front

What happens to a figure when the scale factor is greater than 1?

Back

The figure is enlarged.

Front

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

Back

The figure is reduced.

Front

What is the center of dilation?

Back

The point from which the figure is enlarged or reduced.

Front

If a point (x, y) is dilated by a scale factor of k, what is the new coordinate?

Back

(kx, ky)

Front

What is the y-coordinate in the ordered pair (4, 9)?

Back

9

Front

State the coordinates of the image of point B (4, 9) under a dilation with center at the origin and scale factor of 2.

Back

B' (8, 18)

Front

What does a scale factor of 1 indicate?

Back

The image will be the same size as the pre-image.

Front

If the scale factor is 0.5, what is the effect on the original figure?

Back

The original figure will be reduced to half its size.

Front

What is the formula for finding the new coordinates after dilation?

Back

New coordinates = (scale factor) * (original coordinates)