Graphing Linear Equations: Examples (page 3 of 4)

Sections: Making a T-chart, Plotting the points and drawing the line, Examples

• Graph y = (–5/3)x – 2
• First I'll do the T-chart.

 Since I am multiplying x by a fraction, I will pick x-values that are multiples of 3, so the denominator will cancel out and I won't have fractions. Then I'll plot my points and draw my graph:
• Graph y = 7 – 5x

•  First I'll do the T-chart.
 This equation is an example of a situation in which you will probably want to be particular about the x-values you pick. Because the x is multiplied by a relatively large value, the y-values grow quickly. For instance, you probably wouldn't want to use x = 5 or x = –3. You could pick larger x-values if you wished, but your graph would get awfully tall. And as you can see, the graph is pretty tall already:
• Graph y = 3
• Don't let this one scare you. Yes, there is no "x" in the equation, but that's okay. Just think about it this way: it doesn't matter what x-value you pick; y will always be 3.

 Your T-chart would look something like this:

Then your graph would look like this:

Any time you have a "y equals a number" equation, with no x in it, the graph will always be a horizontal line.

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 Cite this article as: Stapel, Elizabeth. "Graphing Linear Equations: Examples." Purplemath. Available from     http://www.purplemath.com/modules/graphlin3.htm. Accessed [Date] [Month] 2016

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