LINEAR EQUATIONS IN TWO VARIABLES
Chapter 5 introduced the concept of linear slope, a constant that describes
the steepness of a line in the coordinate plane. This chapter explores con-
structing linear equations using the point-slope and slope-intercept formu-
las, expressing equations in standard form, and graphing linear equations
that are expressed in point-slope form.
You need only two things to create the equation of a line: the slope
of that line and one of the points on the line. Now that you know how to
calculate slope (if you don’t, stop right now and work through Problems
5.26–5.39), you can use one of two formulas to create a linear equation:
the point-slope formula or the slope-intercept formula.
After you generate the equation of a line, you can sketch a quick
graph of it (say goodbye to tables of values) and then (if required)
write it in standard form.