Similarity and Dilations

Choose the correct scale factor:

• 2

• 3

• 1/3

• 1/2

Tell whether the transformation is a dilation. Explain.

• No, scale factor isn't the same.

• Yes, scale factor is the same.

Are the triangles similar?

• Yes

• No

Given: PQ || BC.  Find the length of AB.

• 14

• 11

• 16

• 18

Select ALL the true statements about an image after a dilation.

• The image is a different shape than the preimage.

• The image is a different size than the preimage.

• The image has the same angle measures as the preimage.

• The image is similar to the preimage.

• The image has the same side lengths as the preimage.

Rajesh is making pennants in preparation for a school soccer game. He wants the pennants to be similar triangles. Which of these triangles could he use for the pennants?

• QRS and TVW

• QRS and XYZ

• TVW and JKL

• TVW and XYZ

Figure D´E´F´G´ is a dilation with center (0, 0) of figure DEFG. What is the scale factor?

A sequence of transformations is required to map ΔPQR onto ΔP’Q’R’. Which is a possible step?

• A dilation with scale factor 1

• A dilation with scale factor 2

• A dilation with scale factor 3

• A dilation with scale factor 4

Triangle DEF is similar to triangle ABC. What is a sequence of transformations that maps triangle ABC to triangle DEF?

• Reflection then rotation

• Rotation then dilation with scale factor of 2

• Rotation then dilation with scale factor of 0.5

• Rotation then translation

Triangle PQR is the image of triangle JKL after a dilation. Is the dilation an enlargement or a reduction? Explain.

• Enlargement, because the image is larger than the original figure.

• Enlargement, because the image is smaller than the original figure.

• Reduction, because the image is smaller than the original figure.

• Reduction, because the image is larger than the original figure.