Results 1 to 2 of 2

Math Help - Related Rates Triangle

  1. #1
    MHF Contributor
    Joined
    Mar 2010
    From
    Florida
    Posts
    3,093
    Thanks
    5

    Related Rates Triangle

    A surface ship is moving in a straight line horziontally at 20Km/hr. At the same time, a submarine is moving in the same direction at a 15 degree down angle staying directly under the ship. How fast is the submarines altitude decreasing.

    \frac{dx}{dt}=20

    \theta=15

    What equation should I use? I tried Pythagorean identity and sin = y/r. Didn't yield anything promising.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    skeeter's Avatar
    Joined
    Jun 2008
    From
    North Texas
    Posts
    12,060
    Thanks
    894

    Re: Related Rates Triangle

    Quote Originally Posted by dwsmith View Post
    A surface ship is moving in a straight line horziontally at 20Km/hr. At the same time, a submarine is moving in the same direction at a 15 degree down angle staying directly under the ship. How fast is the submarines altitude decreasing.

    \frac{dx}{dt}=20

    \theta=15

    What equation should I use? I tried Pythagorean identity and sin = y/r. Didn't yield anything promising.
    y = x\tan(-15^\circ)
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. [SOLVED] related rates with triangle
    Posted in the Calculus Forum
    Replies: 6
    Last Post: September 23rd 2011, 04:07 PM
  2. related rates #4
    Posted in the Calculus Forum
    Replies: 9
    Last Post: August 17th 2009, 09:38 PM
  3. Rates and Related Rates!!
    Posted in the Calculus Forum
    Replies: 1
    Last Post: April 2nd 2008, 11:53 AM
  4. Related rates, again
    Posted in the Calculus Forum
    Replies: 1
    Last Post: March 24th 2008, 02:49 PM
  5. rates and related rates
    Posted in the Calculus Forum
    Replies: 2
    Last Post: October 29th 2007, 10:51 PM

/mathhelpforum @mathhelpforum