1. The problem statement, all variables and given/known data A 125 lb weight is suspended from the ceiling by means of two perpendicular flexible cables. Find the tension (in pounds) in each cable. There is a picture attached. I'm new at posting so I'll try my best to describe this simple image. There is a line that runs horizontal representing the ceiling. On the left side of the ceiling, there is a line that runs South east at a 55 degree angle ending at the 125lb weight. On the right side of the ceiling there is a line that runs south west at a 40 degree angle ending at the 125lb weight. That is about it. The ceiling and the cables form a triangle. 2. Relevant equations None given 3. The attempt at a solution This is a problem in the vector section of my multivariable calculus book. The solution to a similar problem is given by defining the cables (arbitrarily called T1 and T2) as T1=(T1 cos40)i +(T1sin40)j and T2=(-T2cos55)i +(T2sin55)j. From there the solution states that T1 + T2 + F(force or -125j) = 0. And they solve algebraically. I am having trouble with the concept. I do not want to plug in numbers without knowing why. I would like to know why we use cosine and sine. (I have a vague idea, but not a firm understanding). I would also like to know how to solve the problem. If anyone has an idea, it would be appreciated. I feel as though this is a very basic and simple problem and I would like to get some good insight to it. Thanks in advance.