Suppose a firm is making its location decision and acting in the same manner as firms in the Weber Model. The firm takes three inputs and produces a single output. This output costs $5/unit to transport. To produce one unit of output, the firm uses three units of input 1, four units of input 2 and two units of input 3. If the inputs cost $3, $2 and $4 to ship per unit respectively, what expression will describe the optimal location for the firm?