Graphing Absolute-Value Functions: Examples

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Graphing Absolute-Value Functions (page 2 of 2)

Here are some more examples, with just the T-charts and graphs:

Graph y = | x | + 2

I'll fill in my T-chart, making sure to pick some negative x-values as I go:

T-chart

Then I'll draw my dots and fill in the graph:

y = abs(x) + 2

Graph y = –| x + 2 |

My T-chart:

T-chart

...and my graph:

y = -abs(x + 2)

Graph y = –| x | + 2
Copyright © Elizabeth Stapel 2000-2011 All Rights Reserved

My T-chart:

T-chart

...and my graph:

y = -abs(x) + 2

Graph y = | x² – 3x – 4 |

Without the absolute-value bars, the graph of the quadratic looks like this:

The absolute-value bars will flip that negative part of the graph (the part in the middle, below the x-axis) up into the positive values (above the x-axis).

y = x^2 - 3x - 4

Here's my T-chart:

T- chart

...and here's my graph:

y = abs(x^2 - 3x - 4)

With these graphs, when in doubt, plot more points!

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Cite this article as:

Stapel, Elizabeth. "Graphing Absolute-Value Functions." Purplemath. Available from
http://www.purplemath.com/modules/graphabs2.htm. Accessed

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