Two rays sharing a common endpoint. Angles are typically measured in degrees or radians.

A line segment on the interior of a circle. A chord has both

endpoints on the circle.

A complete circular arc. Circumference also means the distance around the outside of a circle.

(x + 2)(x + 5) = x(x + 5) + 2(x + 5)                       = x · x + x·5 + 2·x + 2·5                       = x2 + 7x + 10

To multiply out the parts of an expression. Distributing is the opposite of factoring.

A transformation in which a geometric figure is reflected across a line, creating a mirror image. That line is called the axis of reflection.

A polygon with six sides.

Perfectly flat and level. For example, the horizon is horizontal. So is the floor and so is this bar.

The side of a right triangle opposite the right angle. Note: The hypotenuse is the longest side of a right triangle.

All positive and negative whole numbers (including zero). That is, the set {... , –3, –2, –1, 0, 1, 2, 3, ...}.

The number that occurs the most often in a list.

5 is the mode of 2, 3, 3, 4, 5, 5, 5

The following are all

monomials: 5x3, 8,

and 4xy.

A polynomial with one term.

A line representing the set of all real numbers. The number line is typically marked showing integer values.

For , the Numerator is 12.

The top part of a fraction.

πThe ratio of the circumference of a circle to its diameter. Pi is written π and is a transcendental number.

3.14159 26535 89793...

An equation relating the lengths of the sides of a right triangle. The sum of the squares of the legs of a right triangle is equal to the square of the hypotenuse.

The likelihood of the occurrence of an event. The probability of event A is written P(A). Probabilities are always numbers between 0 and 1, inclusive.

A polygon with four sides.

A quadrilateral which has a pair of opposite sides which are parallel. The parallel sides are called the bases, and the other two sides are called the legs.