Equation: maximize f(x,y)=x+y Subject to sx+ty<=1 x,y>=0 So the question asks for values of s and t that make the problem infeasible, unbounded, and have an optimal solution. I completed the infeasible with values s=-1 and t=-1. unbounded I got s=2 and t=-4. for the optimal solution I tried using fractions like 1/4 and 1/2 but it does not satisfy sx-ty<=1. Thanks for help!