Similarity and Proportions

Front

What is similarity in geometry?

Back

Similarity in geometry refers to two shapes that have the same shape but may differ in size. Their corresponding angles are equal, and their corresponding sides are in proportion.

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal. It can be expressed as a/b = c/d, where a, b, c, and d are numbers.

Front

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

Back

If two polygons are similar, their corresponding angles are equal.

Front

If a 12-ounce shampoo bottle lasts 16 weeks, how long will an 18-ounce bottle last?

Back

24 weeks.

Front

How do you find the missing side length of similar polygons?

Back

To find the missing side length of similar polygons, set up a proportion using the lengths of corresponding sides.

Front

If a car travels 420 miles in 8 hours, what is its speed in miles per hour?

Back

The speed is 52.5 miles per hour (420 miles ÷ 8 hours).

Front

If a car continues at the same speed, how far will it travel in 12 hours?

Back

630 miles.

Front

What is the scale factor in similar figures?

Back

The scale factor is the ratio of the lengths of corresponding sides of two similar figures.

Front

If the scale factor of two similar triangles is 2:3, what does this mean?

Back

This means that for every 2 units of length in the first triangle, there are 3 units of length in the second triangle.

Front

How do you solve for x in similar triangles?

Back

Set up a proportion using the lengths of corresponding sides and solve for x.