# Chapter 4: Name That Line

**Advanced**Created by: CK-12

**Introduction**

In this chapter you learn about relations defined by \begin{align*}y=mx+b\end{align*}. You will learn how to rewrite an equation given in the form \begin{align*}Ax +By+C=0\end{align*} in the form \begin{align*}y=mx+b\end{align*}. You will learn to graph \begin{align*}y=mx+b\end{align*} by using the point-slope method as well as how to write the equation of a line from the graph by determining the slope and the \begin{align*}y-\end{align*}intercept.

To write the equation of a line, you must know the slope and the \begin{align*}y-\end{align*}intercept of the line. In this chapter you will learn how to calculate the slope of a line from two given points on the line, from a given equation, from a point on the line and the \begin{align*}y-\end{align*}intercept and from the relationship between special lines. In addition, you will learn how to determine the \begin{align*}y-\end{align*}intercept of a line algebraically.

When these basic concepts have been mastered, you will learn how to determine the equation of lines that are parallel and perpendicular to the \begin{align*}x\end{align*} and \begin{align*}y\end{align*} axis or to other lines.

Finally, all of the concepts will be applied to problems that use linear functions as a model.

**Lessons**

In this chapter you will do the following lessons:

- The Slope of a Line from a Graph or from Two Points
- The Equation of a Line in Slope-Intercept Form
- Graphing the Linear Functions \begin{align*}y=mx+b; \ y=a; \ x=a\end{align*}
- Determining the Equation of a line from the Graph
- Parallel and Perpendicular Lines
- Linear Function as a Model

- 4.1.
## The Slope of a Line from a Graph or from Two Points

- 4.2.
## The Equation of a Line in Slope – Intercept Form

- 4.3.
## Quiz I

- 4.4.
## Graphing the Linear Functions y = mx + b; y = a; x = a

- 4.5.
## Determining the Equation of a Line from the Graph

- 4.6.
## Parallel and Perpendicular Lines

- 4.7.
## Quiz II

- 4.8.
## Linear Function as a Model

- 4.9.
## Chapter Test