Proportions, Scale Factor & Similarity

Front

What is a proportion?

Back

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

Front

What is the scale factor?

Back

The scale factor is a number that scales, or multiplies, a quantity. It is the ratio of the lengths of two corresponding sides of similar figures.

Front

What does it mean for two polygons to be similar?

Back

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

Front

What are corresponding sides?

Back

Corresponding sides are the sides of two or more similar figures that are in the same position relative to the figures.

Front

If the scale factor from triangle ABC to triangle DEF is 2, what does this mean?

Back

It means that each side of triangle DEF is twice the length of the corresponding side of triangle ABC.

Front

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

Back

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

Front

What is the relationship between corresponding angles in similar polygons?

Back

In similar polygons, corresponding angles are always equal.

Front

If triangle ABC is similar to triangle DEF and the length of side AB is 6 and side DE is 12, what is the scale factor?

Back

The scale factor is 2.

Front

What is the formula for finding the scale factor between two similar figures?

Back

Scale Factor = Length of a side of the new figure / Length of the corresponding side of the original figure.

Front

If two triangles are similar and one has a side length of 10 and the corresponding side in the other triangle is 5, what is the scale factor?

Back

The scale factor is 1/2.