1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Paralellogram diagonals

  1. Sep 12, 2010 #1
    1. The problem statement, all variables and given/known data
    Find the length of the two diagonals of a paralellogram with the sides (-2,-2) and (-10,-2)

    2. Relevant equations

    3. The attempt at a solution
    What I have tried is, I drew out the 2 vectors, and then drew out their components and used trig to find the angles where the connect. I also found the magnitude of both the vectors.
    Am i on the right track?
  2. jcsd
  3. Sep 12, 2010 #2


    Staff: Mentor

    Not really. If u = <-2, -2> and v = <-2, -10> are your two vectors, a vector that represents the main diagonal of the parallelogram is u + v. The other diagonal is given by u - v.
  4. Sep 12, 2010 #3
    OMG I totally missed that oh man I fail! Thanks so much, I over complicated it!!!!
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook