A petroleum company wants to lay a pipe from one of its tanks to a station across the river. The river is 2 km across, and the station is 9 km downstream. The pipe is laid in two sections; across the river to point B, and on land from point B to the station. Let A be the point on the river bank directly across from the tank. Let the distance AB be x.

(a) Express the total length of the pipeline in terms of x.

(b) It costs $8 per metre to lay the pipe over water and $4 per metre to lay the pipe over land. Locate point B which minimises the cost of laying the pipe.

Answer rating: 100% (QA)

To solve this problem lets break it down into two parts the pipeline across the river and the pipeli... View the full answer