Thumbnail: For some problems it may help to remember that when a right triangle has a hypotenuse of length $$r$$ and an acute angle $$θ$$, as in the picture below, the adjacent side will have length $$r\cos θ$$ and the opposite side will have length $$r\ sin θ$$. You can think of those lengths as the horizontal and vertical "components'' of the hypotenuse. (GNU FDL; Michael Corral).