cos and sec of trig?

Question

when solving for a triangle with given a angel and adjancent side , using cos gives you way of value and sec gives you the right results why . for ex:
21.3 is the angel and 31.6 is the adjacent side
another ex 57.3 is the angel and 135 feets is the side . you try them and let me know
hence, for the first one using cosine gives the results of 29. something degrees and sec gives you the right answer that is 33.9

Answer 1

you might want to post in the HW section because I don't know how Sine, Cosine, and Tangent have to do with non-alcoholic drinks.