a crane at the edge of a dock is supported by a cable 15 meters long, attached to the dock 9 meters long from the base of the crane. if the crane is 6 meters long, what is the acute angle that the crane arm forms with the horizontal?

Answer 1

As I interpret the data, it appears that the law of cosines will provide our answer. We want the supplement to θ, where

15^2 = 6^2+9^2 - 2(6)(9)cosθ
cosθ = -1

Nope, that doesn't work. Maybe you can just describe the figure, giving labels to the points of interest.

Answer 2

180