Algebra Test Helper



The most common way students learn to graph lines is using y=mx + b or the slope intercept method.  This is a great method because it’s straight forward and easy.  However a linear equation must be in y=mx + b form to use the slope intercept method of graphing.  Let’s look at a quick example.  The line 3x -7 = 2y is not in y = mx + b format so we could not use the slope intercept method to graph this line unless we rewrite it into y=mx + b which we can do without too much trouble.  Now let’s take a look at the line y=4x + 1 this line is in slope intercept y=mx + b form so we can easily graph it- how fun!  So how exactly do we graph a line in slope intercept form?  Well all we need to do is follow a few steps.  Ok step 1 is to plot the y-intercept( this is the point the line crosses the y-axis) and this number is the “b” pat of y=mx + b.  In our example y=4x + 1 the y-intercept would be 1.  Now onto our next step and for this we will use the “m” part of y=mx + b.  The “m” part is the slope of the line.  What we do is use the slope(rise/run) to plot a second point.  Specifically we count the rise and run from y-intercept to plot a second point (watch the lesson video to see how this is done).  Lastly we connect the two points we plotted and presto we have a line!  Graphing lines using the slope intercept method is a skill you must master so I really encourage you to relax and watch the lesson video below- good luck!

Did you like this video lesson?  Watch me solve many more problems on graphing lines using the slope intercept method

1. the slope intercept method can be used when linear equations are written in y=mx + b form 2. the first step is to plot the “b” or y-intercept 3. next use the “m” or slope to find a second point 4. draw a line through the two points 5. if a line is not in y=mx + b form you simply can rewrite it such that it is and graph using the slope intercept

Often it’s the easy things we tend to “mess up” and from my experience when students graph one variable lines they make mistakes not because it’s hard rather they just never remember if y = a number or x = a number is a vertical line or horizontal line.  Let’s do a quick review of graphing one variable lines.  If you are asked to graph a line that has the equation x=5 this would be a vertical line that goes through 5 on the x-axis.  Hence x= a number lines are vertical lines that goes through the respective number in...

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