Results 1 to 2 of 2

Math Help - Solving radical equations

  1. #1
    Newbie
    Joined
    Oct 2008
    Posts
    3

    Solving radical equations

    Cable Connections

    The local cable company has a main station located on a stretch of straight coastline. A small island lies twenty miles down the coast from the main office and five miles offshore. In order to supply service to the island, the cable company needs to run underground cable from the main station to a substation on the island. The cost for laying the cable is $30,000 per mile along the coast, but the cost for laying the cable under the ocean is $42,000 per mile. What is the minimum cost for connecting the two stations, and how can this be achieved?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    A riddle wrapped in an enigma
    masters's Avatar
    Joined
    Jan 2008
    From
    Big Stone Gap, Virginia
    Posts
    2,551
    Thanks
    12
    Awards
    1
    Quote Originally Posted by nelle87 View Post
    Cable Connections

    The local cable company has a main station located on a stretch of straight coastline. A small island lies twenty miles down the coast from the main office and five miles offshore. In order to supply service to the island, the cable company needs to run underground cable from the main station to a substation on the island. The cost for laying the cable is $30,000 per mile along the coast, but the cost for laying the cable under the ocean is $42,000 per mile. What is the minimum cost for connecting the two stations, and how can this be achieved?
    Not sure why your heading says "radical equations" but this looks like a classic example for the Pathagorean Theorem.

    Laying cable down the coastline for 20 miles @ $30,000/mi and under the ocean for 5 miles @ $42,000 = $810,000 total cost.

    The hypotenuse of the right triangle formed by the 20 miles down the coast and 5 miles out to the island is about 20.62 miles. This is found by using the Pathagorean Theorem:

    c^2=20^2+5^2
    c\approx20.62

    So, the cost of going under the ocean directly from the main station would be 20.62 \times 42000=865,852

    So, it's $865,852 - $810,000 or $55,852 cheaper going the route of the two legs
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Solving a radical equation.......
    Posted in the Algebra Forum
    Replies: 3
    Last Post: January 24th 2011, 01:48 PM
  2. Solving Radical equations
    Posted in the Algebra Forum
    Replies: 1
    Last Post: March 14th 2010, 06:22 PM
  3. Solving radical equations
    Posted in the Algebra Forum
    Replies: 1
    Last Post: November 12th 2009, 03:58 PM
  4. solving radical equations
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: October 15th 2009, 12:43 AM
  5. Solving Radical Equations
    Posted in the Algebra Forum
    Replies: 1
    Last Post: April 18th 2009, 07:04 AM

Search Tags


/mathhelpforum @mathhelpforum