Similarity and Dilations Flashcard Review

Front

What is a dilation in geometry?

Back

A dilation is a transformation that alters the size of a figure but not its shape, using a scale factor.

Tags

CCSS.8.G.A.3

Front

What does a scale factor of 1/2 indicate in a dilation?

Back

A scale factor of 1/2 means that the new figure is half the size of the original figure.

Tags

CCSS.8.G.A.3

Front

How do you find the coordinates of a point after dilation about the origin?

Back

Multiply each coordinate of the point by the scale factor.

Tags

CCSS.8.G.A.3

Front

If point H is at (6, 6) and is dilated by a scale factor of 1/2, what are the new coordinates?

Back

H' (3, 3)

Tags

CCSS.8.G.A.3

Front

What is the relationship between similar shapes?

Back

Similar shapes have the same shape but may differ in size; their corresponding angles are equal and corresponding sides are proportional.

Tags

CCSS.HSG.CO.B.6

CCSS.8.G.A.2

Front

How do you determine if two shapes are similar?

Back

Two shapes are similar if their corresponding angles are equal and the lengths of their corresponding sides are proportional.

Tags

CCSS.HSG.CO.B.6

CCSS.8.G.A.2

Front

What is the difference between congruence and similarity?

Back

Congruent shapes have congruent corresponding sides and angles; similar shapes have congruent corresponding angles and proportional corresponding sides.

Tags

CCSS.8.G.A.2

Front

If two triangles are similar, how can you find an unknown side length?

Back

Use the ratio of the lengths of corresponding sides to set up a proportion.

Tags

CCSS.HSG.SRT.A.2

Front

If triangle ABC is similar to triangle DEF, and AB = 4, DE = 8, what is the ratio of their corresponding sides?

Back

The ratio is 1:2.

Tags

CCSS.HSG.SRT.A.2

Front

What is the formula for finding the area of similar figures?

Back

The area ratio of two similar figures is the square of the ratio of their corresponding side lengths.