Chapter 4 - An Introduction to Functions - 4-4 Graphing a Function Rule - Practice and Problem-Solving Exercises - Page 259: 40

The graphs are shown below. Changing the k-value vertically shifts the graph up or down.

In the function rule y=|x|+k, changing the value of k, moves the graph up or down. If k is positive the graph moves up, if k is negative the graph moves down. For example, y=|x|+1, k=1 so the graph moves up one unit. And for y=|x|-3, k=-3 so the graph moves down three units.