Scale Factor

Front

What is a scale factor?

Back

A scale factor is a number that scales, or multiplies, some quantity. It is used to determine the proportional relationship between two similar figures.

Front

If the scale factor is greater than 1, what happens to the figure?

Back

The figure is enlarged.

Front

What does it mean for two figures to be similar?

Back

Two figures are similar if they have the same shape but may differ in size. Their corresponding angles are equal, and their corresponding sides are in proportion.

Front

What are corresponding sides?

Back

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

Front

What is the relationship between the angles of similar figures?

Back

All angles in similar figures are congruent.

Front

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

Back

To find the scale factor, divide the length of a side of one figure by the length of the corresponding side of the other figure.

Front

If a rectangle has a length of 10 cm and a width of 5 cm, what is the scale factor if the new rectangle has a length of 20 cm?

Back

The scale factor is 2.

Front

What happens to the area of a figure when the scale factor is doubled?

Back

The area of the figure increases by a factor of the square of the scale factor (in this case, 4 times).

Front

What is a reduction in terms of scale factor?

Back

A reduction occurs when the scale factor is less than 1, resulting in a smaller figure.

Front

If the scale factor of ΔABC to ΔXYZ is 1.5, what does this indicate?

Back

This indicates that the sides of ΔXYZ are 1.5 times longer than the corresponding sides of ΔABC.