# Power Company

• Jan 15th 2009, 01:53 PM
magentarita
Power Company
A power company needs to string a power line between 2 buildings. One building is located on the west side of a river, and the other building is located 3000 ft downriver on the opposite side of the river. The river is 500 ft wide. The power line must run underground on the shore and underwater across the river. The cost to run the line underwater \$50 per foot, and the cost to run the line underground is \$40 per foot.

A) How much does it cost to run 500 feet of wire underground and rest underwater?
B) How much does it cost to run 1000 feet of wire underground and rest underwater?
C) Write an equation/ function for the total cost to run the power line between the 2 buildings in terms of the amount of wire run underground.
• Jan 15th 2009, 04:05 PM
Jhevon
Quote:

Originally Posted by magentarita
A power company needs to string a power line between 2 buildings. One building is located on the west side of a river, and the other building is located 3000 ft downriver on the opposite side of the river. The river is 500 ft wide. The power line must run underground on the shore and underwater across the river. The cost to run the line underwater \$50 per foot, and the cost to run the line underground is \$40 per foot.

A) How much does it cost to run 500 feet of wire underground and rest underwater?
B) How much does it cost to run 1000 feet of wire underground and rest underwater?
C) Write an equation/ function for the total cost to run the power line between the 2 buildings in terms of the amount of wire run underground.

did you draw a diagram?

try it and see if you can see where to go. it involves triangles
• Jan 18th 2009, 06:13 PM
magentarita
ok...
Quote:

Originally Posted by Jhevon
did you draw a diagram?

try it and see if you can see where to go. it involves triangles

Can you draw a diagram for me? I might be able to answer atleast part a alone.
• Jan 18th 2009, 10:21 PM
Jhevon
Quote:

Originally Posted by magentarita
Can you draw a diagram for me? I might be able to answer atleast part a alone.

attached you will find the base diagram (which is just a diagram illustrating the positions of the buildings without considering the power lines) and also the diagram for part (a). i filled in the power lines. take note of the triangle ABC and ABD. note further that ABD is a right-triangle.

i leave it to you to draw the diagram for part (b) and finish the problem if you can