How Do You Find the Cosine of an Angle in a Right Triangle?

What's a trigonometric ratio? It is a ratio between two sides of a right triangle. In this problem, find cosine(A) in the given right triangle. Use the ratio of the adjacent side divided by the hypotenuse to find cos(A). The instructor draws a diagram and labels all the sides and angles. She then explains how to apply the formula to find cos(A).