Start chapters home Start History history History expand_more Community
Community expand_more
menu_open Close
{{ filterOption.label }}
{{ item.displayTitle }}
{{ item.subject.displayTitle }}
No results
{{ searchError }}
Expand menu menu_open home
{{ courseTrack.displayTitle }}
{{ statistics.percent }}% Sign in to view progress
{{ }} {{ }}
search Use offline Tools apps
Login account_circle menu_open
Miscellaneous Functions

Analyzing Graphs of Absolute Value Functions


Absolute Value Function

An absolute value function is any function that contains the absolute value of a variable expression. These functions can also be described as any function that is a transformation of the absolute value parent function, Since the absolute value of an expression is never negative, the graph of the function will always lie on or above the -axis. Note that This means that the points and both lie on As it turns out, these points lie directly across from each other. In fact, this symmetry exists for all inverse input values. Thus, absolute value graphs have a distinct V-shape.

Any function belonging to the absolute value function family can be written using the equation

where and are real numbers and

Graph the absolute value function using a table of values.

Show Solution
To graph the given function using a table of values, we can substitute various -values into the rule and solve for the corresponding -values. The absolute value of a number is always the positive value of that number. For instance, Let's first calculate the -value that corresponds with
We have found that Thus, the point lies on the graph. We can find other points on the graph in the same way.

To draw the graph, we can plot these points, then connect them with a V-shaped curve.


Solving Absolute Value Equations Graphically

An absolute value equation is an equation that contains the absolute value of a variable expression. An example of this kind of equation is

As is the case with most equations, these can be solved graphically. This is done by moving all terms except the constant term to one side. The function, which is the non-constant side of the equation, is then graphed and the solution(s) to the equation are found as the point(s) on the graph having the -coordinate that equals the constant.

Solve the equation graphically.

Show Solution

When solving an equation graphically, the first step is to rearrange the equation so that the constant term is alone on one side. The left-hand side of the equation can now be expressed as a function, We'll draw the graph of

The solutions to the equation are the -coordinates of the points on the graph that have the -coordinate

The equation has the solutions and We can verify the solutions by testing them in the equation. We'll start with
Since makes a true statement, it is a solution to the equation. Next, we'll verify in the same way.

Since makes a true statement, it is also a solution. Thus, the equation has the solutions

{{ 'mldesktop-placeholder-grade-tab' | message }}
{{ 'mldesktop-placeholder-grade' | message }} {{ article.displayTitle }}!
{{ grade.displayTitle }}
{{ exercise.headTitle }}
{{ 'ml-tooltip-premium-exercise' | message }}
{{ 'ml-tooltip-programming-exercise' | message }} {{ 'course' | message }} {{ exercise.course }}
{{ 'ml-heading-exercise' | message }} {{ focusmode.exercise.exerciseName }}
{{ 'ml-btn-previous-exercise' | message }} arrow_back {{ 'ml-btn-next-exercise' | message }} arrow_forward