To start with trying simplify any equation, you need to first see if the top part of the equation and the bottom part can be factorized. Fortunately the top part and bottom part of the equation are both quadratic equations that can be factorized. ((x^2)+4x) can be factorized into x(x+4) and the bottom part of the equation can be factorized into (x+4)(x-1). Now we have the equation x(x+4)/(x+4)(x-1). There is now two common factors (x+4) on the top part of the equation and bottom part of the equation, therefore they can cancel out. And we are now left with the simplified equation x/(x-1).