1. The problem statement, all variables and given/known data 3y(t)+2=x(t) 2. Relevant equations k1y1(t) + k2y2(t) + 2(k1+k2) = k1x1(t)+k2x2(t) 3. The attempt at a solution I know the system is non linear but I cannot explain why. It has something to do with 2(k1+k2) but I am unsure.