# Lesson Plan: Right Triangle Trigonometry: Solving for a Side Mathematics • 11th Grade

This lesson plan includes the objectives, prerequisites, and exclusions of the lesson teaching students how to find the value of a missing side length in a right triangle by choosing the appropriate trigonometric ratio for a given angle.

#### Objectives

Students will be able to

• find a missing side length in a right triangle (given a figure) using the sine, cosine, and tangent ratios where the unknown is at the top of the ratio,
• find a missing side length in a right triangle (given a figure) using the sine, cosine, and tangent ratios where the unknown is at the bottom of the ratio,
• find all the lengths of a right triangle,
• draw a figure for a question and use this to find unknown lengths,
• interpret and solve real-life and applied problems to find unknown lengths using right triangle trigonometry.

#### Prerequisites

Students should already be familiar with

• right triangles and the Pythagorean theorem.

#### Exclusions

Students will not cover

• solving for an angle using trigonometry.