If I know the radius, is there a way to find out or estimate the angle theta in my drawing? http://i.imgur.com/773OLxI.png

Question

anonymous · Answer

the line is tangent to the circle

anonymous · Answer

I don't know the answer, but if you google it, you will probably find the answer.

anonymous · Answer

I already tried and I couldn't find anything useful

anonymous · Answer

what on earth is $\theta$ supposed to represent?  to have an angle you need two lines

anonymous · Answer

|dw:1362937906668:dw|

anonymous · Answer

|dw:1362937968010:dw| to be exact I have a hovercraft shaped like that (rectangle and semicircle) and I wish to estimate the angle theta form by the tangent line