Definitions

**All definitions come from MathPower9 McGraw-Hill Ryerson either from the back of the book or in Chapter 5 from pages 237 to 293.

CARTESIAN COORDINATE SYSTEM ** A system for graphing points as ordered points on a grid made up of two perpendicular number lines.

In a direct variation, the ratio of corresponding values of the variables For example, if //d // varies directly as //t //, then the constant of variation, //k //, is given by //d/t // = //k or d //=//kt //
 * CONSTANT OF VARIATION **

A relationship between two variables in which one variable is a constant multiple of the other. When graphed, the line should pass through the origin. For example, //y // = 2//x //
 * DIRECT VARIATION **

The set of first elements in the ordered pairs the x in (//x, y //)
 * DOMAIN **

The individual numbers of a set (//x, y //)
 * ELEMENTS **

Differences between consecutive y-values in tables with evenly spaced x-coordinates. In a linear relation, the first differences are constant.
 * <span style="font-family: 'Arial','sans-serif';">FIRST DIFFERENCES **

A relationship between two variables that does not fit a straight line when graphed
 * <span style="font-family: 'Arial','sans-serif';">NON-LINEAR RELATIONS **

The point of intersection of the x-axis and the y-axis on the coordinate grid
 * <span style="font-family: 'Arial','sans-serif';">ORIGIN **

A relationship between two variables in which one variable is a constant multiple of the other, plus some constant. When graphed, the line does not pass through the origin For example, if //<span style="font-family: 'Arial','sans-serif';">y // varies partially as //<span style="font-family: 'Arial','sans-serif';">x //, then //<span style="font-family: 'Arial','sans-serif';">y // = //<span style="font-family: 'Arial','sans-serif';">kx // + //<span style="font-family: 'Arial','sans-serif';">c //, where //<span style="font-family: 'Arial','sans-serif';">k // and //<span style="font-family: 'Arial','sans-serif';">c // are real numbers and //<span style="font-family: 'Arial','sans-serif';">c // ≠ 0.
 * <span style="font-family: 'Arial','sans-serif';">PARTIAL VARIATION **

The set of second elements the ordered pairs the y in (//<span style="font-family: 'Arial','sans-serif';">x, y //)
 * <span style="font-family: 'Arial','sans-serif';">RANGE **

An identified relationship between variables that may be expressed as a table of values, a graph, or an equation. This is because the order of the two values or elements is important.
 * <span style="font-family: 'Arial','sans-serif';">RELATION **

The horizontal number line of the Cartesian grid.
 * //<span style="font-family: 'Arial','sans-serif';">X //****<span style="font-family: 'Arial','sans-serif';">-AXIS **

The first number in the ordered pair describing a point on a Cartesian plane. For example, for the point P(3,-8), 3 is the //<span style="font-family: 'Arial','sans-serif';">x //-coordinate.
 * //<span style="font-family: 'Arial','sans-serif';">X //****<span style="font-family: 'Arial','sans-serif';">-COORDINATE **

//<span style="font-family: 'Arial','sans-serif';">**X** //<span style="font-family: 'Arial','sans-serif';">**-INTERCEPT** The point at which the graph crosses the x-axis. A point on the graph where the //<span style="font-family: 'Arial','sans-serif';">y // value is 0, is the x-intercept. The //x//-coordinate of the point where a line or curve crosses the //x//-axis.

The vertical number line of the Cartesian grid.
 * //<span style="font-family: 'Arial','sans-serif';">Y //****<span style="font-family: 'Arial','sans-serif';">-AXIS **

The second number in the ordered pair describing a point on a Cartesian grid. For example, for the point P(3,-8), -8 is the //<span style="font-family: 'Arial','sans-serif';">y //-coordinate
 * //<span style="font-family: 'Arial','sans-serif';">Y //****<span style="font-family: 'Arial','sans-serif';">-COORDINATE **

Where the graph crosses the y-axis. A point on the graph where the //<span style="font-family: 'Arial','sans-serif';">x // value is 0, is the y-intercept.
 * //<span style="font-family: 'Arial','sans-serif';">Y //****<span style="font-family: 'Arial','sans-serif';">-INTERCEPT **