Simultaneous equations are equations that involved two or more unknown variables. There must be as many equations as the number of unknown variables in order for us to solve the problem. There are two types of simultaneous equations, the first is liner and the second is mixed. For linear simultaneous equations, please refer to linear simultaneous equations. In this example, we will show you how to design a program that can solve mixed simultaneous equations, that is , one linear equation and one quadratic equation. The interface is as shown below: