As a result of the water crisis in Lasa, the Lasa Department of Water, with the assistance of their engineers and accountants decided to build a water line that has to be cost effective. The water line will be built from point A to D, as shown in Figure 3. The cost differs, given as such: 3k from A to B, 2k from B to C, and k from C to D, where the cost per kilometer is in dollars (for simplicity, let k =1). The accountants worked together with the engineers to minimize the total cost. Use Lagrange multipliers to find x. y and z such that the total cost C' will be minimized 2km B 1km C D X V Z 10km Figure 3: The water line plan