Solving Triangles Teacher Resources

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.

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.

In this triangles practice activity, learners sharpen their problem solving skills as they solve 6 story problems.

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.

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...

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...

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. 

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...

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.

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.

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.

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...

In this video, Sal proves the Law of Sines by using the SOH-CAH-TOA model and setting up equivalent ratios.

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...

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...

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. 

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...

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...

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.

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...

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...