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**