Consider the following predator-prey system where x and y are in millions of creatures and t represents time in years:
dy/dt=2x-xy
dy/dt=-4y+xy
1. Show that (4,2) is the nonzero equilibrium solution .
2. Find an expression for dy/dx

Question

Consider the following predator-prey system where x and y are in millions of creatures and t represents time in years:
dy/dt=2x-xy
dy/dt=-4y+xy
1. Show that (4,2) is the nonzero equilibrium solution .
2. Find an expression for dy/dx

anonymous · Answer

The first must be dx/dt!

anonymous · Answer

That is what I confused too-.-

anonymous · Answer

Do you know how to solve?

anonymous · Answer

Let me have try

anonymous · Answer

I need the second part
Thank you

anonymous · Answer

it must be wrong!you can see it: http://en.wikipedia.org/wiki/Lotka%E2%80%93Volterra_equation

anonymous · Answer

Which one is the real $\frac{dx}{dt}$?

anonymous · Answer

Also, $$\frac{dy}{dx} = \dfrac{\left(\dfrac{dy}{dt}\right)}{\left(\dfrac{dx}{dt}\right)}$$