# Lesson Plan: Right Triangle Trigonometry: Solving for an Angle Mathematics

This lesson plan includes the objectives, prerequisites, and exclusions of the lesson teaching students how to find a missing angle in a right triangle using the appropriate trigonometric function given two side lengths.

#### Objectives

Students will be able to

• label the sides and angle of a right triangle,
• find an unknown angle measure in a right triangle (given a figure) using the sine, cosine, and tangent ratios and their inverse functions,
• draw a figure for a question and use it to find an unknown angle in a right triangle,
• interpret and solve real-life and applied problems using right triangle trigonometry.

#### Prerequisites

Students should already be familiar with

• the Pythagorean theorem,
• converting degrees into degrees, minutes, and seconds,
• solving for a side in a right triangle using the trigonometric ratios (sine, cosine, and tangent),
• the sum of interior angles in a polygon,
• properties of polygons,
• similar and congruent triangle properties.

#### Exclusions

Students will not cover

• solving for a side only using trigonometry,
• using the term inverse trigonometric functions,
• non-right triangle trigonometry,
• angles of elevation and depression.