• Absolute value: The distance between a number and zero on the number line.   The symbol for absolute value is shown in the equation |−8| = 8.
• Coordinates: An ordered pair, (x, y), that locates a point in a plane.
• Inequality: Any mathematical sentence that contains the symbols > (greater than), < (less than), ≤ (less than or equal to), or ≥ (greater than or equal to).
• Integers: The set of whole numbers and their opposites {… − 3, −2, −1, 0, 1, 2, 3, …}.
• Negative numbers: The set of numbers less than zero.
• Opposite number: Two different numbers that have the same absolute value. Example: 4 and −4 are opposite numbers because both have an absolute value of 4.
• Ordered Pair: A pair of numbers, (x, y), that indicate the position of a point on the Cartesian Plane.
• Origin: The point of intersection of the vertical and horizontal axes of a Cartesian plane. The coordinates of the origin are (0, 0).
• Positive number: The set of numbers greater than zero.
• Rational number: The set of numbers that can be written in the form  where a and b are integers and b ≠ 0.
• Sign: a symbol that indicates whether a number is positive or negative.   Example: in −4, the (−) sign shows this number is read “negative four”.
• x-axis: The horizontal number line on the Cartesian coordinate plane.
• x-coordinate: The first number of in ordered pair; the position of a point relative to the vertical axis.
• y-axis: The vertical number line on the Cartesian coordinate plane.
• y-coordinate:   The second number in an ordered pair; the position of a point relative to the horizontal axis.

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