Algebra I Chapter 3 Vocabulary

Domain

The set of all possible input values (x-values) of a function.

Range

The set of all possible output values (y-values) of a function.

Discrete Domain

A set of input values that consists of only certain numbers in an interval.

We list out the numbers in the domain in brackets.

Continuous Domain

A set of input values that consist of all numbers in an interval.

We write the domain as an inequality.

Function

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

Function Notation

Another name for y denoted as f(x) and read as "f of x".

Increasing

A function's graph moves up as x moves to the right.

Decreasing

A function's graph moves down as x moves to the right.

Independent Variable

The variable that represents the input values (x-values) of a function.

Dependent Variable

The variable that represents output values of a function.

Linear Function

A function whose graph is a nonvertical line.

Nonlinear Function

A function that does not have a constant rate of change whose graph is not a line.

Relation

A collection of ordered pairs that connects two sets taking one number from each set.

Slope

The rate of change between any two points on a line.

Slope-Intercept Form

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

Standard Form

A linear equation written in the form Ax+By=, C where A, B, and C are real numbers and A and B are not both zero.

x-intercept

The point where the graph intersects the x-axis.

y-intercept

The point where the graph intersects the y-axis.

Slope Formula

Positive Slope

Negative Slope

Zero Slope

Horizontal lines have a slope of zero.

Undefined Slope

Vertical lines have an undefined slope.

Equation of a Vertical Line

x=a, where a is the x-intercept

Equation of a Horizontal Line

y=b, where b is the y-intercept

Vertical Line Test

Given a graph, this test is used to determine whether the relation is a function.