Similar Figures and Scale Factor

Front

What are similar figures?

Back

Similar figures are shapes that have the same shape but may differ in size. Their corresponding angles are equal, and their corresponding sides are in proportion.

Tags

CCSS.8.G.A.2

CCSS.HSG.CO.B.6

Front

What is a scale factor?

Back

A scale factor is a number that scales, or multiplies, some quantity. In the context of similar figures, it is the ratio of the lengths of corresponding sides.

Tags

CCSS.7.G.A.1

Front

If two similar figures have a scale factor of 1/4, what does this mean?

Back

It means that each side of the smaller figure is 1/4 the length of the corresponding side of the larger figure.

Front

How do you find the missing side length in similar figures?

Back

To find the missing side length, set up a proportion using the scale factor and the known side lengths.

Front

If the scale factor from figure A to figure B is 5, what is the relationship between their side lengths?

Back

The side lengths of figure B are 5 times longer than the corresponding side lengths of figure A.

Tags

CCSS.7.G.A.1

Front

What is the scale factor if the lengths of two similar figures are 10 and 100?

Back

The scale factor is 1/10, meaning the smaller figure's sides are 1/10 the length of the larger figure's sides.

Tags

CCSS.7.G.A.1

Front

If the length of a side in a smaller figure is 4 and the corresponding side in a larger figure is 16, what is the scale factor?

Back

The scale factor is 4, as 16 divided by 4 equals 4.

Tags

CCSS.7.G.A.1

Front

How do you express the scale factor as a fraction?

Back

The scale factor can be expressed as a fraction by taking the length of a side in the smaller figure over the length of the corresponding side in the larger figure.

Tags

CCSS.7.G.A.1

Front

What is the scale factor if the lengths of two similar figures are 3 and 12?

Back

The scale factor is 1/4, as 3 divided by 12 equals 1/4.

Tags

CCSS.7.G.A.1

Front

If the scale factor is 10, what can you say about the areas of the two similar figures?

Back

The area of the larger figure is 10^2 = 100 times greater than the area of the smaller figure.

Tags

CCSS.7.G.A.1