A company sells X units of a product whose profits function is given by the quadratic model P(X) =60X-X^2 = X(60-X)

A) How many units should the company sell in order to maximize their profits

B) What will be the maximum profit if the # of units found in part (A) were sold

C) what is the maximum number of units the business can sell and still make a pofit

Once again i am stopped by quadratic functions please help me