(Solved): part b A small office unit is to contain \( 900 \mathrm{ft}^{2} \) of floor space. A simplified mode ...

A small office unit is to contain \( 900 \mathrm{ft}^{2} \) of floor space. A simplified model is shown in the figure. (a) Use an equation to express the length \( y \) of the building in terrms of the width \( x \). \[ y=\frac{900}{x} \] (b) If the walls cost s200 per running foot, use an equation to express the cost \( c \) of the walls in terms of the width x. (Disregard the wall space above the doors and the thickness of the wails.)