Writing a linear function as a periodic function

Question

I want to write a mathematical expression of this graph

First thing that I notice is it's actually $f(t) = 6-4t$ with it domains restricted at $[0,2]$. Can I write expression of $x(t)$ as $x(t)=x(t+2)=6-4t$? Or is there any more "right" way to write the expression of $x(t)$?

Thank you