Scale Factor & Using 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 find the missing side of a shape using a scale factor?

Back

To find the missing side, multiply the known side by the scale factor.

Front

If the scale factor is 1:3, what does this mean?

Back

This means that for every 1 unit of measurement in the smaller figure, there are 3 units in the larger figure.

Front

What happens to a figure if the scale factor is greater than 1?

Back

If the scale factor is greater than 1, the new figure will be an enlargement.

Front

What happens to a figure if the scale factor is less than 1?

Back

If the scale factor is less than 1, the new figure will be a reduction.

Front

How do you determine the scale factor between two similar shapes?

Back

To determine the scale factor, divide the length of a side of the larger shape by the corresponding side of the smaller shape.

Front

What is the scale factor from shape A to shape B if shape B is twice as large?

Back

The scale factor from shape A to shape B is 2.

Front

If triangle ABC has sides of length 4, 6, and 8, and triangle DEF has sides of length 8, 12, and 16, what is the scale factor from triangle ABC to triangle DEF?

Back

The scale factor is 2.

Front

What is the relationship between the areas of two similar figures and their scale factor?

Back

The area of the larger figure is equal to the square of the scale factor times the area of the smaller figure.

Front

If the scale factor from a small triangle to a large triangle is 3, what is the ratio of their perimeters?

Back

The ratio of their perimeters is also 3.