According to economists, this episode of great recession was resulted from a sudden busting of house bubble in US, where the house bubble was caused by rapid growth of improper regulation on sub-prime mortgages (Merriam 2009; Wang 2009; Whitney 2007).
When working with equations that have two variables, the coordinate plane is an important tool. It's a way to draw pictures of equations that makes them easier to understand. To create a coordinate plane, start with a sheet of graph or grid paper. Next, draw a horizontal line.
2 METHOD. A general equation that governs a continuous state variable, y(t) , can be written in the form: dy/dt = f(y,x,t). where dy/dt is the derivative of y with respect to time, t, and x represents the other state variables that define the system.