see attachment

Solutions
The given predator-prey model is
ẋ = x(a− by) (1)
ẏ = y(−c+ dx) (2)
a. The nullclines are obtained when the given differential equations are
set to zero. Therefore
ẋ = x(a− by) = 0 (3)
ẏ = y(−c+ dx) = 0 (4)
x-nullclines:
From equ.(3), we get x = 0 or a - by = 0
y-nullclines
From equ.(4) we get y = 0 or -c + dx = 0
Figure 1: Nullclines
b. The stationary points are the...