Increase or Decrease
| A line with a positive slope points up to the right.
|
A line with a negative slope points down to the right.
|
A linear function is increasing when the \(x\)-values increase and the \(y\)-values increase.
 This line is increasing. An increasing line has a positive slope \((m>0)\). |
A linear function is decreasing when the \(x\)-values increase and the \(y\)-values decrease.
 This line is decreasing. A decreasing line has a negative slope \((m<0)\). |
| A linear function is constant when the \(x\)-values increase and the \(y\)-values remain the same.
This line is a horizontal line. A horizontal line has zero slope \((m=0)\). |
A linear function is undefined if the \(x\)-values are constant as the \(y\)-values vary.
This line is a vertical line. A vertical line has undefined slope. |
