Domain & Range

Domain

The set of all possible input values (x-values), measured from left to right on the graph.

Range

The set of all possible output values (y-values), measured from bottom to top on the graph.

X-intercept

The point where the graph crosses the horizontal axis (y=0).

Y-intercept

The point where the graph crosses the vertical axis (x=0).

Increasing Interval

The section of the graph where the line goes UP as you move from left to right.

Decreasing Interval

The section of the graph where the line goes DOWN as you move from left to right.

Positive Interval

The portion of the graph that is located ABOVE the x-axis (y>0).

Negative Interval

The portion of the graph that is located BELOW the x-axis (y<0).

Linear Function

A function that forms a perfectly straight line (y=mx+b).

Non-Linear Function

A function that curves or changes direction, such as a Parabola or Absolute Value.

Parent Function

The simplest version of a function family (e.g., y=x2 for quadratics).

Above the x-axis

Positive

Below the x-axis

Negative

Heading Uphill

Increasing

Heading Downhill

Decreasing