Similar Figures and Proportions

Front

What are similar figures?

Back

Two figures that have the same shape but may have different sizes.

Front

What does it mean for two figures to be congruent?

Back

Two figures that are the same shape and size.

Front

What are corresponding sides?

Back

Sides in two similar figures that are in the same position relative to each other.

Front

What are corresponding angles?

Back

Angles in two similar figures that are in the same position relative to each other.

Front

If two triangles are similar, what can we say about their angles?

Back

All corresponding angles are congruent (equal).

Front

If the sides of two similar figures are in the ratio 2:3, what is the ratio of their areas?

Back

The ratio of their areas is 4:9.

Front

What is the scale factor in similar figures?

Back

The ratio of the lengths of corresponding sides.

Front

If triangle ABC is similar to triangle DEF, and AB = 4 cm, DE = 6 cm, what is the scale factor?

Back

The scale factor is 4:6 or 2:3.

Front

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

Back

Set up a proportion using the lengths of corresponding sides.

Front

What is the relationship between the perimeters of similar figures?

Back

The ratio of their perimeters is the same as the ratio of their corresponding side lengths.