Geometry - Chapter 5 Vocabulary

Ambiguous

something that has more than one interpretation or conclusion

Angle

formed by two rays joined at a common endpoint

Counterexample

An example showing that a generalization has at least one exception

Cosine Ratio

In a right triangle, the ____ ratio of an acute ∠A is the adjacent leg divided by the hypotenuse

Equilateral

all sides have equal length

Hypotenuse

The longest side of a right triangle

Inverse Sine

When the ratio between the length of the side opposite the reference angle and the length of the hypotenuse are known, sin −1 (raised to the negative one) can be used to find the measure of the reference angle

Inverse Cosine

When the ratio between the length of the side adjacent the reference angle and the length of the hypotenuse are known, cos −1 (raised to the negative one) can be used to find the measure of the reference angle

Inverse Tangent

When the ratio between the lengths of the legs of a right triangle is known, tan −1 (raised to the negative one) can be used to find the measure of the reference angle

Isosceles

Having two sides of equal length

Leg

the two sides of a right triangle that form the right angle

Pythagorean Triple

Any three positive integers a, b, and c that make the relationship a 2 + b 2 = c 2 true

Reference Angle

The given acute angle in a right triangle

Right Triangle

A triangle that has one right angle

Sine Ratio

In a right triangle, the _ ratio of an acute angle is the opposite leg divided by the hypotenuse

Slope Angle

The acute angle a line forms with the x-axis on a coordinate graph

Tangent Ratio

In a right triangle, the ____ ratio of an acute angle is the opposite leg divided by the adjacent leg

Theta

a Greek letter that is often used to represent the measure of an angle

Trigonometric Ratio

examples are sine, cosine, and tangent.