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

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

Back

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

Front

If the scale factor is 2, what does that imply about the sizes of the two figures?

Back

It implies that the second figure is twice the size of the first figure.

Front

What is the scale factor if a side of a smaller triangle measures 3 cm and the corresponding side of a larger triangle measures 9 cm?

Back

The scale factor is 9 cm / 3 cm = 3.

Front

If the scale factor from figure A to figure B is 4, what is the scale factor from figure B to figure A?

Back

The scale factor from figure B to figure A is 1/4, which is the reciprocal of 4.

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, and their corresponding angles are equal while their corresponding sides are in proportion.

Front

If a triangle has a scale factor of 3, and one of its sides is 5 cm, what is the length of the corresponding side in the similar triangle?

Back

The length of the corresponding side in the similar triangle is 5 cm * 3 = 15 cm.

Front

What is the relationship between the areas of two similar figures when the scale factor is known?

Back

The ratio of the areas of two similar figures is equal to the square of the scale factor.

Front

If the scale factor is 1/2, how does this affect the dimensions of the original figure?

Back

The dimensions of the original figure will be halved.

Front

What is the scale factor if the lengths of corresponding sides of two similar figures are 10 cm and 5 cm?

Back

The scale factor is 5 cm / 10 cm = 1/2.