Question 55007
I think you meant f(x)=2x-5, which is the same as y=2x-5.  All you have to do is to create two ordered pairs (points) so you can plot them and then connect with a straight edge (e.g., ruler) as two points define a straight line.  For example, if you substitute 0 for x, you get y=-5, and if x=5, then y=0.  The graph is:
{{{graph(200,200,-5,5,-10,5,2x-5)}}}