Unit B: Right Triangles
Chapter 4:Trigonometry

Lesson 1: The Tangent Ratio

Have you ever wondered how engineers and astronomers determine the distances to locations inaccessible such as the distance to the opposite side of a gorge, or the distance between two stars? One of the most important tools they have is trigonometry. Trigonometry includes the study of the relationships between angle measures and side lengths in triangles. Trigonometry is invaluable to navigators, scientists, and builders.

Trigonometry The study of the relationship between side lengths and angle measures in triangle

 
Suppose you wanted to determine the height of a flag pole. How would you do it? Is it possible to determine its height without actually measuring it?

The tangent ratio corresponds to the relationship between an angle measure and two side lengths in a right triangle. The tangent ratio can be used to determine an unknown side length or an unknown angle measure in a right triangle.

   The Goal

Here are the things you will do in this lesson:

• Learn how to determine the tangent ratio for right triangles.
• Learn how the tangent ratio can be used to determine unknown side lengths and angles.

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