Introductory Algebra

Glossary

Unit 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 (x 1 , y 1 ) and (x 2 , y 2 ), 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.

Return to Introductory Algebra Created by James Q. Jacobs