< Back to Videos NATION Question 3 of 3 < PREVIOUS QUI A developer wishes to construct a duplex (two residential units that are side-by-side, sharing a common wall). The interior floors are to be congruent rectangles with areas of 1200 square feet. The outside wall and the common wall that separates the residences are constructed from cinderblocks. Let / represent the length of one residential unit of the duplex and w represent its width. Choose a function, in terms of I, that could be used to determine the total length of cinderblocks needed for all walls (including both the exterior and common walls).​