Dilations With a Center Not at the Origin

Choose the correct scale factor:

• 2

• 3

• 1/3

• 1/2

The __________ is the ratio of a length of the new figure to the corresponding length on the original figure.

• reduction

• enlargement

• scale factor

• center of dilation

Triangle ABC is dilated to produce triangle A'B'C' with scale factor 3/4 . Which describes the relationship between the two triangles?

• Triangle A'B'C' is an enlargement of triangle ABC

• Triangle A'B'C' is a reduction of triangle ABC

• Triangle A'B'C' is a mirror image of triangle ABC

What does the scale factor do in a dilation?

• Tells you how much the image grows or shrinks

• Tells you what the center of dilation is

• There's not enough information here to answer this

• Nothing, it's unnecessary information

What is the scale factor?

• k = 2

• k = 1/2

• k = 4

• k = 1/4

In the diagram below, CD is the image of AB after a dilation of scale factor k with center E. Which ratio is equal to the scale factor k of the dilation?

• EC : EA

• BA : EA

• EA : BA

• EA : EC

A line segment is dilated by a scale factor of 2 centered at a point not on the line segment. Which statement regarding the relationship between the given line segment and its image is true?

• The line segments are perpendicular, and the image is one-half of the length of the given line segment.

• The line segments are perpendicular, and the image is twice the length of the given line segment.

• The line segments are parallel, and the image is twice the length of the given line segment.

• The line segments are parallel, and the image is one-half of the length of the given line segment

A three-inch line segment is dilated by a scale factor of 6 and centered at its midpoint. What is the length of its image?

• 9 inches

• 2 inches

• 15 inches

• 18 inches

On the graph below, point A(3, 4) and BC with coordinates B(4, 3) and C(2, 1) are graphed. What are the coordinates of B' and C' after BC undergoes a dilation centered at point A with a scale factor of 2?

• B'(5,2) and C'(1, -2)

• B'(6, 1) and C'(0, -1)

• B'(5, 0) and C'(1, -2)

• B'(5, 2) and C'(3, 0)

If the scale factor is greater than one, the new figure will be

• reduction

• enlargement

• scale

• not proportional