Similarity

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 congruent, and their corresponding sides are in proportion.

Front

What is a scale factor?

Back

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

Front

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

Back

The figure undergoes an enlargement.

Front

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

Back

The figure undergoes a reduction.

Front

What happens to the angles of similar figures?

Back

The angles of similar figures are congruent.

Front

What happens to the sides of similar figures?

Back

The sides of similar figures are proportional.

Front

How do you find the missing side of a similar figure?

Back

Use the ratio of the corresponding sides and the scale factor to set up a proportion and solve for the missing side.

Front

What is dilation in geometry?

Back

Dilation is a transformation that alters the size of a figure but keeps its shape, making it larger or smaller.

Front

What is the relationship between the scale factor and the area of similar figures?

Back

The area of similar figures is proportional to the square of the scale factor.

Front

If triangle A is similar to triangle B with a scale factor of 3, what is the ratio of their areas?

Back

The ratio of their areas is 3^2 = 9.