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A rectangular garden of area 320 square feet is to be surrounded on three sides by a brick wall costing $10 per foot and on one side by a fence costing $6 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 e feet