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Homework Help: Related Rates problem.

  1. Aug 31, 2011 #1
    Could someone verify my answer for this question?

    13m ladder is leaning against a wall.
    If the top of the ladder slips down the wall at a rate of 2m/s.
    How fast will the foot be moving away from the wall when the top is 5m from the ground?

    My answer:

    use pythagoras to set up equation x^2 + y^2 = 13^2

    Then I differentiate this implicitly and get the equation 2x dx/dt + 2y dy/t = 0

    Then I fill in the values and get 5/6 m/s.

    Is this correct?
  2. jcsd
  3. Aug 31, 2011 #2


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    Homework Helper

    That is correct. I did it another way though, using a formula for dh/db.
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