KY.HS.G.9a Remediation

Multiple Choice

What is a dilation?

• The process of making a polygon larger or smaller without changing its shape

• The process of making a polygon move up, down, left, or right without changing its shape or size

• The process of making a polygon flip over an invisible line without changing its shape or size

• The process of making a polygon turn along quadrants without changing its shape or size

Dilation

-A dilation is a transformation that produces an image that is the same shape as the original, but is a different size

-When a dilation occurs, the pre-image and image are considered to be similar but NOT congruent.

Dilation

• If a dilation creates a larger image, it is called an enlargement because it stretches the original image

• If a dilation creates a smaller image, it is called a reduction because it shrinks the original image

Multiple Choice

Which best describes an enlargement?

• stretches the original image

• shrinks the original image

Multiple Choice

Which best describes a reduction?

• stretches the original image

• shrinks the original image

Real Life Examples of Dilations

Real Life Examples of Dilations

Real Life Examples of Dilations

The Scale Factor

• We use the scale factor(sf) to help describe and determine the type of dilation that takes place

• If sf > 1; the dilation is an enlargement

• is sf < 1; the dilation is a reduction

• if sf = 1; the image and pre-image are the exact same

Multiple Choice

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

Multiple Select

Which scale factors would increase an image?

• $$\frac{3}{2}$$

• $$\frac{1}{2}$$

• $$3.5$$

• $$\frac{2}{1}$$

• 5
  

Multiple Choice

If line AB is dilated to form line A'B', what is true about the two lines?

• The lines are perpendicular.

• The lines are parallel.

• The lines intersect.

Multiple Select

Which scale factors shrink an image?

• $$0.5$$

• $$\frac{3}{4}$$

• $$1$$

• $$\frac{2}{1}$$

• $$\frac{3}{2}$$

Multiple Select

What are the properties of dilations?

• Changes the size of an object

• Changes the shape of an object

• Changes one side but not the others

• Changes all the sides equally

• Changes angle measures

Line Dilations

When lines are dilated, then lines are parallel.

Line Dilations

When lines are dilated, the length of the image or new line is larger or smaller by the scale factor. Multiply the length of the original line by the scale factor.

Multiple Choice

Line AB is dilated by a factor 3.5 to form line A'B'. If the length of segment AB is 5 inches, what is the length of of segment A'B' ?

• 8.5 inches

• 17.5 inches

• 1.4 inches