Introductory Algebra Glossary

Chapter Three

ordered pair

A pair of numbers written within parentheses in which the order of the numbers is important.

table of values

An organized way of displaying ordered pairs.

x-axis

The horizontal number line in a rectangular coordinate system.

y-axis

The vertical number line in a rectangular coordinate system.

rectangular coordinate system

The x-axis and y-axis placed at a right angle at their zero points, also called the Cartesian coordinate system.

quadrant

One of the four regions in the plane determined by a rectangular coordinate system.

origin

The point at which the x-axis and y-axis of a rectangular coordinate system intersect.

coordinate on a number line

Each number on a number line is called the coordinate of the point that it labels.

plot

To locate an ordered pair on a rectangular coordinate system.

graph of an equation

The set of all points that correspond to all of the ordered pairs that satisfy an equation. The graph of a linear equation in two variables is a straight line.

x-intercept

The point where a graph intersects the x-axis.

y-intercept

The point where a graph intersects the y-axis.

function

A set of ordered pairs (relation) in which each value of the first component x corresponds to exactly one value of the second component y

subscript notation

A way of indicating two nonspecific ordered pairs, such as (x1, y1) and (x2, y2), that satisfy a particular equation relating x and y.

slope

The ratio of the change in y to the change in x along a line.

rise

The vertical change between two points on a line, the change in y-values.

run

The horizontal change between two points on a line, the change in x-values.

parallel lines

Two lines in the same plane that never intersect.

perpendicular lines

Two lines that intersect to form a right angle.

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Created by James Q. Jacobs

Superstition Mountain CampusCentral Arizona College