Scale Factor and Corresponding Parts

Front

What is a scale factor?

Back

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

Front

How do you find the scale factor between two similar triangles?

Back

To find the scale factor between two similar triangles, divide the length of a side of one triangle by the length of the corresponding side of the other triangle.

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 as long as the corresponding side of triangle ABC.

Front

What does it mean for two figures to be similar?

Back

Two figures are similar if they have the same shape but not necessarily the same size. Their corresponding angles are equal, and their corresponding sides are in proportion.

Front

If triangle ABC has a side length of 4 cm and triangle XYZ has a corresponding side length of 2 cm, what is the scale factor from ABC to XYZ?

Back

The scale factor from triangle ABC to triangle XYZ is 1/2.

Front

What is the corresponding side length of triangle DEF if the scale factor from triangle ABC to DEF is 2 and the side length of ABC is 5 cm?

Back

The corresponding side length of triangle DEF would be 10 cm.

Front

In similar triangles, how do you identify corresponding parts?

Back

Corresponding parts are identified by matching angles and sides based on their position in the triangles. For example, the angle opposite a side in one triangle corresponds to the angle opposite the same side in the other triangle.

Front

If triangle A has sides of lengths 3, 4, and 5, and triangle B is a scaled copy with a scale factor of 3, what are the side lengths of triangle B?

Back

The side lengths of triangle B would be 9, 12, and 15.

Front

What is a scaled copy?

Back

A scaled copy is a figure that is similar to another figure but is either larger or smaller by a certain scale factor.

Front

If triangle ABC is similar to triangle XYZ with a scale factor of 2/5, and the length of side AB is 10 cm, what is the length of side XY?

Back

The length of side XY would be 4 cm.