Science:Math Exam Resources/Courses/MATH100/December 2010/Question 05/Statement

Full-Solution Problems. In questions 2-8, justify your answers and show all your work. If a box is provided, write your final answer there. Simplification of answers is not required unless explicitly requested.

Cobblestone Engineering has been contracted to build a bridge and a pathway from Calculus City located at point A on the shoreline of a 6km wide river that runs west to east, to a power plant at point B on the opposite shoreline, 8km to the east. It costs 40 dollars per km to build a bridge over the river and 20 dollars per km to build a pathway along a shoreline. How should the company proceed in order to minimize the total cost? Be sure to justify that the total cost is indeed a minimum.