Lesson 9-1, 9-2, 9-3, 9-4, 9-5, 9-6, 9-7

Rate of Change

A change in one quantity with respect to another quantity.

Slope-Intercept Form

A linear equation in the form y = mx + b, where m is the slope and b is the y-intercept.

System of equations

A set of two or more equations with the same variables.

Function

A special relation in which each element of the domain is paired with exactly one element in the range.

Direct Variation

A special type of linear equation that describes rate of change. A relationship such that as x increases in value, y increases or decreases at a constant rate.

Function Notation

A way to name a function that is defined by an equation. For example, y = 3x - 8 would be written as f(x) = 3x - 8.

Linear Equation

An equation in which the variables appear in separate terms and neither variable contains an exponent other than 1. The graph of this type of equation is a straight line.

Linear Relationship

Relationship that has straight line when graphed.

Function Rule

The operation performed on the input of a function.

Constant Rate of Change

The rate of change that occurs between any two data points in a linear relationship that is the same or constant.

Slope

The ratio of the rise, or vertical change, to the run, or horizontal change. This describes the steepness of a line.

Constant of Variation

The slope, or rate of change, in the equation y=kx, represented by k.

Independent Variable

The variable in a function with a value that is subject to choice.

Dependent Variable

The variable in a relation with a value that depends on the value of the other variable in the relation.

X-intercept

The x-coordinate of a point where a graph crosses the x-axis.

Y-intercept

The y-coordinate of a point where a graph crosses the y-axis.

Function Table

This organizes the input, rule, and output of a function.

Substitution

Use algebraic methods to find an exact solution of a system of equations.

Vertical Line Test

When a line is drawn on the graph of a relation, and it passes through no more than one point on the graph for each value of x in the domain, determining that the relation is a function.