In order to solve this exercise, you need to remember the following Transformation Rules for Functions:
1. When:
[tex]-f(x)[/tex]The function is reflected across the x-axis.
2. When:
[tex]f(-x)[/tex]The function is reflected across the y-axis.
In this case, you have this function:
[tex]f\mleft(x\mright)=|4x|-6[/tex]If this function is reflected across the y-axis, you can apply the second Transformation Rule for Functions explained before. Then, you get that the answer is:
[tex]f(x)=|-4x|-6[/tex]