Chapter 7 Vocabulary

Similar

Figures that have the same shape but not necessarily the same size

Extremes

In the proportion a/b = c/d, a and d are the extremes. If the proportion is written as a:b = c:d, the extremes are in the first and last positions.

Means

In the proportion a/b = c/d, b and c are the means. If the proportion is written as a:b = c:d, the means are in the two middle positions.

Cross Products

In the statement a/b = c/d, the product of the means bc and the product of the extremes ad are called the cross products.

Ratio

a comparison of two numbers by division Can be written as: a/b, a:b, or a to b.

Proportion

an equation that states that two ratios are equal

Indirect Measurement

any method that uses formulas, similar figures, and/or proportions to measure an object.

Scale

is the ratio of any length in the drawing to the corresponding actual length.

Scale Drawing

represents an object as smaller than or larger than its actual size.

Similarity ratio

the ratio of the lengths of the corresponding sides of two similar polygons

Similar polygons

two polygons whose corresponding sides are in proportion and corresponding angles are congruent