A rectangular garden of area 408 square feet is to be surrounded on three sides by a brick wall costing $12 per foot and on one side by a fence costing $5 per foot. That is, two sides of equal length will consist of brick walls, and the other two sides of equal length will consist of one brick wall and a fence. Find the dimensions of the garden such that the cost of the materials is minimized. To minimize costs, the lengths of the sides consisting of a fence and a brick wall should be feet and the lengths of the perpendicular sides, which are only made from brick walls, should be feet