Drawing the Boltzmann distribution Watch
The most accurate way is always to draw it as a bell curve, as in physics.
Might be a good one to ask your chemistry teacher.
I think in any case, drawing the actual graph is the safest option, unless they specifically ask for the graph in the way you described.
I can only think of it as possibly having straight lines if you were to draw the graph of the gradient function, not the actual graph itself.