A vertical translation of a function f(x) is:
[tex]g(x)=f(x)+k[/tex]If k is a positive number, the translation is done upward and if it's negative, then it's done downward.
So, if our function is
[tex]y=f(x)=-\frac{2}{9}\mleft|x\mright|-7[/tex]And we want to translate it vertically 2 units down, we have to substract 2 from the parent function f(x). Let g(x) be the translated function:
[tex]\begin{gathered} g(x)=f(x)-2 \\ g(x)=-\frac{2}{9}\mleft|x\mright|-7-2 \\ g(x)=-\frac{2}{9}|x|-9 \end{gathered}[/tex]The last one I wrote is the translated function.