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: Parallelogram with coordinates

  1. Feb 28, 2008 #1
    1. The problem statement, all variables and given/known data

    Parallelogram ABCD is given, with A(2,4), B(5,7), C(12,8). Find the coordinates of D(x,y).

    2. Relevant equations

    3. The attempt at a solution

    Sorry but, I don't have any idea.
  2. jcsd
  3. Feb 28, 2008 #2
    here it is a hint, although you haven't shown any work at all! do u know how to find the end points C(x2,y2) of a segment if you are given the first point say A(x1,y1), and another point in the segment say B(x,y), and a ratio, say k. ? well the formula is

    x=(x1+kx2)/(1+k), same for y.
    in your problem, you probably know that the diagonals of a regular paralelogram bisect each other.. so what u have to do is first find the coordinates of the point where the diagonals bisect each other, and then you will end up with an idenitcal problem that i explained above!
  4. Feb 29, 2008 #3
    Thank you very much. It helped. D(9,5)
  5. Feb 29, 2008 #4
    It looks fine, although i personally haven't checked it!
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook