Curated OER
Finding the Area of an Equilateral Triangle
The problem seems simple: find the area of the equilateral triangle whose sides are each length 1. In fact, this same problem is solved in 8th grade, addressing a different Common Core standard, using the formula for area of a triangle...
Teach Engineering
Stay in Shape
Using their knowledge of right triangles, pupils find out how far a ship is from a light house. Class members determine how far around the world a ship would be sailing at a constant speed.
Illustrative Mathematics
Two Wheels and a Belt
Geometry gets an engineering treatment in an exercise involving a belt wrapped around two wheels of different dimensions. Along with the wheels, this belt problem connects concepts of right triangles, tangent lines, arc length, and...
Education Development Center
Similar Triangles
Model geometric concepts through a hands-on approach. Learners apply similar triangle relationships to solve for an unknown side length. Before they find the solution, they describe the transformation to help identify corresponding sides.
101 Questions
Sacre Coeur Funicular
Rise to the challenge of trigonometry. Watching a video of an ascending funicular at the Sacre Coeur in Paris sets the stage for a challenging task. Young mathematicians use a given diagram, along with the concepts of slope and...
Illustrative Mathematics
Satellite
Learners practice relating rules of trigonometry and properties of circles. With a few simplifying assumptions such as a perfectly round earth, young mathematicians calculate the lengths of various paths between satellite and...
101 Questions
Marine Ramp
Boat ramps move with waves and changes in water level. Scholars decide on the proper length for a ramp so the angle connecting both sides is appropriate. They visualize the situation and use a simulation to view the results with their...
Illustrative Mathematics
Converse of the Pythagorean Theorem
Use the given tasks and detailed teacher's commentary to introduce your 8th graders to the Pythagorean theorem and its converse. Embedded links to information about Egyptian geometry make your presentation interesting. Consider...
101 Questions
Catcher to 2nd
Who's on second? Young mathematicians use a diagram of a baseball field to find the distance a catcher must throw to reach second base. A brief video of such a play during a baseball game sets the stage for the assignment.
Curated OER
Access Ramp
Just about every public building that your students are familiar with has an access ramp which complies with ADA requirements. As it turns out, designing such a ramp is an excellent activity to incorporate slope, the Pythagorean Theorem,...
5280 Math
Pythagorean Triples
From Pythagorean triples to the unit circle. Learners use the Pythagorean Theorem to find Pythagorean triples and then relate their work to the unit circle in a fun algebra project. Their discovery that x^2+y^2 is always equal to one on...
Varsity Tutors
Varsity Tutors: Hotmath: Practice Problems: Right Triangles and Trigonometry
Twenty-five problems cover the topic of right triangles and trigonometry in different settings. They are given with each step to the solution cleverly revealed one at a time. You can work each step of the problem then click the "View...
Oswego City School District
Regents Exam Prep Center: Special Right Triangles
A collection of lessons, practice activities, and a teacher resource that will aid your exploration and understanding of special right triangles.
Lawrence Hall of Science
The Math Page: Trigonometry: Trignometry of Right Triangles
Here is a site that clearly and thoroughly explains the trigonometry of a right triangle, including finding the values of all six trig functions given a single value. There are example problems solved, problems for the student to...
Lawrence Hall of Science
The Math Page: Trigonometry: Solve Right Triangles
Here is a site that clearly and thoroughly explains how to solve right triangles for any missing side or angle given any two pieces other sides or angles. There are example problems solved, problems for the student to attempt, and...
Interactive Mathematics
Interactive Mathematics: The Right Triangle and Applications
Learn how to "solve" a right triangle and apply the concept to real world situations using angles of elevation and depression.
Analyze Math
Analyze Math: Special Triangles Used in Trigonometry
The trigonometry tutorial investigates special triangles. The activity includes isosceles right triangles and 30-60-90 triangles. The examples show how to obtain the six trigonometric ratios of the special angles using special triangles.
TeachEngineering
Teach Engineering: Trigonometry via Mobile Device
Students investigate the relationships between angles and side lengths in right triangles with the help of materials found in the classroom and a mobile device.
Texas Instruments
Texas Instruments: Sin, Cos, and Tan of Right Triangles
In this activity, students explore a right angled triangle and its trigonometric concepts. They investigate the trigonometric ratios for the angles of the triangle.
Varsity Tutors
Varsity Tutors: Hotmath: Graphing Calculator Practice: Right Triangles and Trigonometry
Practice using your graphing calculator for solving right triangle trigonometry and non-right triangle trigonometry. If you get stumped or if you would like to check your work, then select the View Solution button, which is located...
Curated OER
Trigonometry Realms
Excellent site reviewing the realms of Trigonometry. Topics Include the trig functions, graphs, right triangles and much more.
TeachEngineering
Teach Engineering: Trig River
Students learn about and use a right triangle to determine the width of a "pretend" river. Working in teams, they estimate of the width of the river, measure it and compare their results with classmates.
Lawrence Hall of Science
The Math Page: Trigonometry
Concepts in Trigonometry are explained and illustrated here by a member of the math department at Borough of Manhattan Community College.
TeachEngineering
Teach Engineering: You've Got Triangles!
Students learn about trigonometry, geometry and measurements while participating in a hands-on interaction with LEGO MINDSTORMS NXT technology. First they review fundamental geometrical and trigonometric concepts. Then, they estimate the...