On the other hand a quadratic equation is an equation of the form ax^2+bx+c where a eq 0. A combination of a linear and a quadratic forms a perfect system of equations or a pair of simultaneous equation. It is possible to solve such a system through the substitution method. Examples of Quadratic simultaneous equation . 3x^2+4x-2=0,x+y=9; x^2+x ...