Problems 1 and 2 deal with the predator–prey system

that corresponds to Fig. 9.3.1.

Starting with the Jacobian matrix of the system in (1), derive its linearizations at the two critical points (0 , 0) and (75 , 50). Use a graphing calculator or computer system to construct phase plane portraits for these two linearizations that are consistent with the “big picture” shown in Fig. 9.3.1.

dx dt dy dt 200x - 4xy, -150y + 2xy (1)