Proportions and Similarity

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal.

Front

How do you solve a proportion?

Back

To solve a proportion, cross-multiply the terms and then isolate the variable.

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, meaning their corresponding angles are equal and their corresponding sides are proportional.

Front

What is the relationship between corresponding sides of similar figures?

Back

The corresponding sides of similar figures are proportional.

Front

If 13 out of 20 homes have a personal computer, how many homes would you expect to have one on a street with 60 homes?

Back

39 homes.

Front

What is the formula for finding the scale factor between two similar figures?

Back

The scale factor is found by dividing the length of a side of one figure by the length of the corresponding side of the other figure.

Front

What is the significance of the scale factor in similar figures?

Back

The scale factor indicates how much larger or smaller one figure is compared to another.

Front

If two polygons are similar, what can be said about their areas?

Back

The ratio of their areas is equal to the square of the ratio of their corresponding sides.

Front

What is the definition of congruent figures?

Back

Congruent figures are figures that have the same shape and size.

Front

How can you determine if two triangles are similar?

Back

Two triangles are similar if they satisfy one of the following criteria: AA (Angle-Angle), SSS (Side-Side-Side), or SAS (Side-Angle-Side).