In this paper we will study the problem of drawing graphs with a minim
um number of slopes. We will show that the minimum number of slopes ne
eded to draw a complete graph of n vertices is n. We will also prove t
hat for a complete graph of n vertices to be drawn using only n slopes
its vertices must form a convex polygon. Finally, we will present an
algorithm which checks whether a complete graph of n vertices can be d
rawn using only slopes from a given set of n slopes.