How can you find the critical points of the a predator prey model and solve the linear comparisonsystem corresponding to each critical point?
Then sketch thetrajectories in the vicinity of each?
Yes, there is only one critical point, which is the one you found. I'm afraid I don't know what "solving the linear comparison" refers to. The tangent plane to the surface $\displaystyle z(x, y)$ at that point is going to be $\displaystyle z = c$ for some constant c, because the surface is flat at a critical point. I don't know what else to say about it.