This document discusses how to graph linear equations in a coordinate plane. It defines a linear equation as one whose graph is a line and provides the standard form of a linear equation as ax+by=c. It explains that solutions to linear equations are ordered pairs that make statements true when substituted into the equation. To graph a linear equation, you create a domain of at least three convenient values, solve the equation for those values, and plot the points. Examples are given of graphing the equations y=b, x=a, y=3x-2, y=2.5, and x=-4. The vertical line test is introduced to determine if an equation represents a function.