30 liters of the 40% acid solution is attained by mixing the 25% solution with the 50% solution.
(a) Write the system of equations in which one equation signifies amount of final mixture needed and other represents percent of acid in final mixture. Let x and y represent amounts of 25% and 50% solutions, respectively.
(b) Use the graphing utility to graph two equations in part (a) in same viewing window. As amount of 25% solution increases, how amount of 50% solution changes?
(c) How much of solution is needed to attain specified concentration of final mixture?