Relative to angle A, this is how the sides of a right triangle would be labeled. |
The cosine of angle A equals the length of the adjacent side divided by the length of the hypotenuse.
We could write:
cos(A) = adj / hyp
So, for example, if the length of the adjacent side was 8 and the length of the hypotenuse was 10, then we would write:
cos(A) = 8 / 10
cos(A) = 0.8000