# Geometry Chap. 12 Vocab

## 15 terms

### 30-60-degree Right Triangle

Each congruent triangle formed by drawing an altitude to a side of an equilateral triangle

### 45-degree Right Triangle

An isosceles right triangle

### AA Triangle SImilarity

Two triangles are similar if two angles of one triangle are congruent to two corresponding angles of the other

### Constant of proportionality

The number represented by the ratio of similitude

### contraction

the dilation when absolute value of k is greater than 0 but less than 1

### Extremes

in a proportion a/b+c/d, the first and fourth terms, a and d

### Mean Proportional

the two means of a proportion

### Means

in a proportion a/b+c/d the second and third terms, b and c

### Proportion

an equation that states that two ratios are equal

### Pythagorean Theorem

If a triangle is a right triangle, then the square of the length of the longest side is equal to the sum of the squares of the lengths of the other two sides

### Pythagorean Triple

A set of three integers that can be the lengths of the sides of a right triangle

### Ratio of Similitude

The ratio of the lengths of corresponding sides

### Ratio

A comparison of two numbers or two like quantities by division (e.g., the ratio of girls to boys is two to three, 2/3, 2 to 3, or 2:3)

### Similar

All pairs of corresponding angles are congruent and the ratio of the lengths of all pairs of corresponding sides are equal

### SSS Similarity Theorem

Two triangles are similar if the three ratios of corresponding sides are equal