# Solving Triangles Teacher Resources

Find Solving Triangles lesson plans and worksheets
Showing 21 resources
Lesson Plan
West Contra Costa Unified School District

#### Introduction to Trigonometric Functions

For Teachers 9th - 12th
Scholars first learn the definitions of the sine ratio, the cosine ratio, and the tangent ratio. After mastering these definitions, they use the new information to solve triangles.
Interactive
CK-12 Foundation

#### Determination of Unknown Triangle Measures Given Area: Jib Sheets

For Students 10th - 12th Standards
Solving triangles is a breeze. Young boat enthusiasts solve problems involving triangles in the context of sails on a boat. They must apply different strategies, including the Law of Cosines and area formulas.
Worksheet
Curated OER

#### Leveled Problem Solving Triangles

For Students 4th - 6th
In this triangles practice activity, learners sharpen their problem solving skills as they solve 6 story problems.
Worksheet
Curated OER

#### Using the Law of Sines and the Law of Cosines to Solve Triangles

For Students 10th - 12th
In this trigonometry worksheet, learners apply the Law of Sines and Cosines to solving for missing sides of a triangle. There are 5 questions with an answer key.
Instructional Video4:22
Curated OER

#### How Do You Solve a Problem Using Indirect Measurement with Shadows?

For Teachers 6th - 10th
Using indirect measurement, this video shows viewers how to find the height of a flagpole. The lecturer employs drawings as well as proportions to solve this problem, explaining each step. A useful resource to aid struggling learners and...
Instructional Video4:57
Curated OER

#### How Do You Solve a Problem Using Indirect Measurement with Shadows?

For Teachers 6th - 12th
Using indirect measurement, this video shows viewers how to find the height of a flagpole. The lecturer employs drawings as well as proportions to solve this problem, explaining each step. A useful resource to aid struggling learners and...
Lesson Plan
Curated OER

#### The Law of Sines and the Law of Cosines

For Teachers Higher Ed
In this college level trigonometry worksheet, students apply the Law of Sines and the Law of Cosines to solve triangles. The four page worksheet contains forty-four problems. Solutions are not provided.
Lesson Plan
Curated OER

#### Triangle Inequality Theorem

For Teachers 8th - 10th
Students use the inequality theorem to solve triangles and their properties. In this geometry lesson, students are given spaghetti of different lengths and asked to create triangles. They conclude the necessary length needed to make a...
Lesson Plan
Curated OER

#### I'm So Sorry I Ate Chocolate

For Teachers 6th
Sixth graders investigate the magnitudes of the sides and angles of a triangle. They determine the proof of the Sine Rule before using it to solve triangles. They compare the Sine Rule to the Cosine Rule in this unit of lessons.
Lesson Plan
Curated OER

#### An Application of Congruence

For Teachers 9th - 10th
Students solve triangles using the properties if congruency. In this geometry lesson, students apply congruent and similar figures to solve real world and math problems. They show they are able to follow instructions.
Worksheet
Curated OER

#### Law of Sines and Law of Cosines

For Students 11th - 12th
In this Pre-calculus/Trigonometry activity, students use the laws of sines and cosines to solve triangles. The four page activity contains thirteen problems. Answers are not included.
Instructional Video9:27

#### Law of Cosines

For Students 11th - Higher Ed
Sal derives the Law of Cosines using a method similar to the wayward ship captain word problem he solves in another video. This video provides a good review of using the SOH-CAH-TOA model, the Pythagorean Theorem, some of the basic trig...
Instructional Video6:34

#### Proof: Law of Sines

For Students 11th - Higher Ed
In this video, Sal proves the Law of Sines by using the SOH-CAH-TOA model and setting up equivalent ratios.
Lesson Plan
EngageNY

#### The Side-Angle-Side (SAS) and Side-Side-Side (SSS) Criteria for Two Triangles to Be Similar

For Students 9th - 10th Standards
Playing with mathematics can invoke curiosity and excitement. As pupils construct triangles with given criteria, they determine the necessary requirements to support similarity. After determining the criteria, they practice verifying...
Lesson Plan
EngageNY

#### The Angle-Angle (AA) Criterion for Two Triangles to Be Similar

For Teachers 9th - 10th Standards
What do you need to prove triangles are similar? Learners answer this question through a construction exploration. Once they establish the criteria, they use the congruence and proportionality properties of similar objects to find...
Lesson Plan
EngageNY

#### Using Trigonometry to Find Side Lengths of an Acute Triangle

For Students 9th - 10th Standards
Not all triangles are right! Pupils learn to tackle non-right triangles using the Law of Sines and Law of Cosines. After using the two laws, they then apply them to word problems.
Lesson Plan
EngageNY

#### Applying the Laws of Sines and Cosines

For Students 9th - 10th Standards
Breaking the law in math doesn't get you jail time, but it does get you a wrong answer! After developing the Law of Sines and Cosines in lesson 33 of 36, the resource asks learners to apply the laws to different situations. Pupils must...
Lesson Plan
EngageNY

#### Sine and Cosine of Complementary Angles and Special Angles

For Students 9th - 10th Standards
Building trigonometric basics here will last a mathematical lifetime. Learners expand on the previous lesson in a 36-part series by examining relationships between the sine and cosine of complementary angles. They also review the ratios...
Lesson Plan
Curated OER

#### Algebra 2 & Trigonometry Practice: Law of Sines

For Teachers 9th - 12th
In this law of sines worksheet, students solve 9 multiple choice and short answer problems.  Students use the law of sines to missing side lengths and angles of triangles.
Interactive
Curated OER

#### Law of Sines or Sine Rule

For Students 9th - 12th
In this online math worksheet, students construct triangles and squares by utilizing the sine rule. This excellent resource allows the students to check their answers, and to get "hints" should they run into difficulties. A terrific...
Lesson Plan
Curated OER

#### Using Trigonometry

For Teachers 5th
Fifth graders explore the use of trigonometry to find unknown sides and angles in right-angled triangles, taking the concepts that were developed in the previous unit and looking at different ways of practicing the new skills. Students...