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Two possibilities for its x component?

  1. Sep 25, 2009 #1
    1. The problem statement, all variables and given/known data

    You are given a vector in the xy plane that has a magnitude of 85.0 units and a y component of -50.0 units.?

    The two possibilities for its x component are + and - 68.74.

    Assuming the x component is known to be positive, specify the vector which, if you add it to the original one would give a resultant vector that is 70.0 units long and points entirely in the -x direction.

    Magnitude = ?
    Direction = ? degree

    2. Relevant equations

    3. The attempt at a solution

    I found the first part of the problem which was "What are the two possibilities for its x component?" But I can't get the right answer for the second part. I'm doing this online so I know if I get it wrong or right.
  2. jcsd
  3. Sep 25, 2009 #2


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    Welcome to PF!

    Hi alexoftennis! Welcome to PF! :wink:
    From the first part, you have a vector (x,y), which you need to subtract from the vector (-70,0).

    Just use vector (component-wise) addition. :smile:
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