Similar Figures & 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 the lengths of their corresponding sides are proportional.

Front

What is a scale factor?

Back

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

Front

If two figures are similar and the scale factor is 2, what does that mean?

Back

It means that each side of the larger figure is twice the length of the corresponding side of the smaller figure.

Front

How do you find the missing side of similar figures?

Back

To find the missing side, set up a proportion using the lengths of the corresponding sides of the similar figures.

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal.

Front

If figure A has a side length of 4 and figure B has a corresponding side length of 10, what is the scale factor from A to B?

Back

The scale factor is 10/4 = 2.5.

Front

What does it mean if two figures are congruent?

Back

Congruent figures are identical in shape and size, meaning all corresponding sides and angles are equal.

Front

What is the relationship between ratios and scale factors?

Back

Scale factors are a specific type of ratio that compares the lengths of corresponding sides of similar figures.

Front

If a triangle has sides of lengths 3, 4, and 5, what is the ratio of the sides?

Back

The ratio of the sides is 3:4:5.

Front

Marvin's son is 3 ft tall and casts a shadow of 1 ft. If Marvin casts a shadow of 2.5 ft, how tall is Marvin?

Back

Marvin is 7.5 ft tall.