Answer:
Given a function f(x), the function f(x) + k will be translated k units down if k<0. In this case, if we want to produce a vertical translation by 4 units down of the function f(x) = 2x, therefore the new function is:
f(x) = 2x - 4.
Now, we can graph the function like we normally do. Attached you will find the graph made with the help of a graphing calculator.