1. The problem statement, all variables and given/known data Hello guys, I have a physic class this session and I'm self-teaching myself most of the material. It's going not too bad so far but I have come across a form of solving I have not seen before and would like to understand how it works. I have the data and the answer, I just don't know how to get the answer from the equation. This is the last part of a problem I have to solve that deal with the moment of a force about an edge. 2. Relevant equations For easier format, here is a picture: http://unwantedcreations.com/img/physic_1.png [Broken] First line is λ of the edge Second line are the coordinate of the point of application of force F third line are the components x, y and z of the force F. in case you don't get it at all, here is the problem and solution: Problem Solution 3. The attempt at a solution Ok so I think I get where -25.363 come from, if you take 0.99228 * -1.8 * 14.2 it does make -25.363, but where does -10.5678 comes from? No idea. Thank you for your time guys.