Graphing a Linear Equation
Using Slope Intercept Form
Now that you've completed a lesson on graphing slope you
are finally ready to graph linear equations.
There are several different ways to graph linear equations. You've already learned how to graph using a
table of values. That's okay for the beginner, but it can be a little time consuming.
Using slope intercept form is one of the quickest and easiest ways to graph a linear equation.
Before we begin, I need to introduce a little vocabulary. We are going to talk about x and y intercepts.
An x intercept is the point where your line crosses the x-axis. The y intercept is the point where your line crosses the y-axis.
We are only going to focus on the y intercept in this lesson, but you'll need to know x intercept for later.
Let's look at an example:
Slope intercept form is used when your linear equation is written in the form:
y = mx+b
x and y are your variables. m will be a numeral, which is your slope. b will also be a numeral and
this is the y-intercept.
In this form only (when your equation is written as y = ....) the coefficient of x is the slope and
the constant is the y intercept.
Let's look at a few examples and I promise that you'll LOVE this new way of graphing!
Example 1
Example 2
Here's a quick summary of this lesson:
Rules for Graphing Using Slope Intercept Form
Your y intercept is always the first point that you plot on the line. Your point will always be
(0, b).
Then use your slope to plot your next point.
If you have two points, you can draw a straight line and this is the line that represents your equation.
Any point on that line is a solution to the equation.
Tip: You have to be very accurate in plotting your points and drawing your lines in order to be able
to read your graph to find other solutions!
Ok... ready to practice?
Click here to move onto the practice problems! Good Luck!
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