So here is a picture I quickly made in photoshop that has the problem: [PLAIN]http://img21.imageshack.us/img21/9406/trigproblem.png [Broken] The rectangle's dimensions are known. (w & h) So it follows that the angle, "@", and the diagonal, "d", is also known. The width between the two black lines, "g", is known too. (I actually "slid" that line down to the end of the black line(The "bottom" one).) Also the black lines themselves are of the same length. Basically everything that is in red is known and I need either x OR y in terms of the other "knowns." Now in the paper that I drew this, I labeled more things such as all the possible angles that I saw or could create. I used law of cosines for that non-right triangle in the middle made up of d, y, and the length of one of the black lines. But I didn't label them on this picture since that would really clutter it up. I figured all those other things could be derived with the information from this picture and maybe even more that I missed. I was hoping someone could help me find a relationship that gives me x OR y, since w is known, I just need one or the other. This seems, at first, a doable trig problem, but when I started working on it, I found that it is not so simple. So I would definitely appreciate any help on this problem. This is not a homework or some sort of hard teaser problem that was assigned in class. This popped up while I was doing my research work and I need to find "x" so that I can write finish writing my code for my research. And if you need any more details, please ask. Thanks in advance.