Rule

Transformations of Absolute Value Functions

The same types of transformations that create new linear functions, also do the same for absolute value functions. They affect absolute value functions in the same way as well. However, since linear functions and absolute value functions have some significant differences, the transformations might look different graphically.
Rule

Translation

By adding some number to every function value,
a function graph is translated vertically.
A graph is translated horizontally by subtracting a number from the input of the function rule.
Note that the number, is subtracted and not added. This is so that a positive leads to a translation to the right, which is the positive -direction.
Rule

Reflection

A function is reflected in the -axis by changing the sign of all function values:
Graphically, all points on the graph move to the opposite side of the -axis, while maintaining their distance to the -axis.
A graph is instead reflected in the -axis, by moving all points on the graph to the opposite side of the -axis. This occurs by changing the sign of the input of the function.
Notice that the vertex of the graph changes location when it does not lie on the line of reflection.
Rule

Stretch and Shrink

A function graph is vertically stretched or shrunk by multiplying the function rule by some constant :
All vertical distances from the graph to the -axis are changed by the factor Thus, preserving any -intercepts.
By instead multiplying the input of a function rule by some constant
its graph will be horizontally stretched or shrunk by the factor Since the -value of -intercepts is they are not affected by this transformation.
Exercises