Khan Academy
Khan Academy: Right Triangle Word Problems
Solve word problems by modeling real-world (and not-so-real) situations as right triangles and using trigonometry.
Illustrative Mathematics
Illustrative Mathematics: G C, G Srt Setting Up Sprinklers
In this task, students must decide where to place sprinklers on a lawn so that the maximum area of the lawn will be watered. To solve it, they must find areas of sectors of circles and use trigonometric ratios to solve right triangles....
Khan Academy
Khan Academy: Special Right Triangles
Use your knowledge of 30-60-90 and 45-45-90 triangles to solve some problems.
Khan Academy
Khan Academy: Solve for a Side in Right Triangles
Given one side length and an acute angle in a right triangle, find another side using trigonometry. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Lawrence Hall of Science
The Math Page: Trigonometry: The 30 60 90 Right Triangle
Here is a site that clearly and thoroughly explains the trigonometry of the 30-60-90 right triangle. There are example problems solved, problems for the student to attempt, and answers to the student problems. Point this site out to...
Discovery Education
Discovery Education: Web Math: Calculate a Right Triangle
WebMath offers a java applet that allows you to input information about a right triangle, and then solves the triangle for any of the missing pieces of information. It also gives a detailed solution using the information that you provided.
Curated OER
Zona Land: Right Triangle Solver 1
A java applet that will solve a right triangle when you provide information for angle D and its opposite side d.
Khan Academy
Khan Academy: Solve for a Side in Right Triangles
Given one side length and an acute angle in a right triangle, find another side using trigonometry.
Purple Math
Purplemath: Right Triangle Word Problems
Demonstrates how to translate, set up, and solve basic right-triangle word problems.
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...
CK-12 Foundation
Ck 12: Geometry: 30 60 90 Right Triangles Problem Solving
[Free Registration/Login may be required to access all resource tools.] Identify special triangles and use the characteristics of 30-60-90 triangles in problem solving.
Khan Academy
Khan Academy: Special Right Triangles
Use your knowledge of 30-60-90 and 45-45-90 triangles to solve some problems. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
University of Saskatchewan (Canada)
University of Saskatchewan: Geometry
The University of Saskatchewan's Department of Mathematics and Statistics provides high school students with online tutorials and exercises on what they deem some of the most important topics in geometry: Triangles, and Circles and Other...
Other
Dans Math: Lessons: Trigonometry
College professor Dan Bach reviews basic trig concepts, including trig functions, right triangles, circles, radians, and polar coordinates. Site includes animated graphs and detailed examples.
Illustrative Mathematics
Illustrative Mathematics: G Srt Ask the Pilot
In the July 2013 issue of United Airlines' Hemisphere Magazine, a pilot responded to a question about how far in the distance he could see at different altitudes. The solution involved right triangles, lines of tangency to a circle, and...
Khan Academy
Khan Academy: Solve Triangles Using the Law of Sines
Solve missing triangle measures using the law of sines. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
University of Cambridge
University of Cambridge: Nrich: Triangles to Tetrahedra
Given an unlimited number of a specific type of equilateral, isosceles, and right triangles create as many tetrahedra as are possible. Includes printout.
CK-12 Foundation
Ck 12: Trigonometry: Pythagorean Theorem for Solving Right Triangles
[Free Registration/Login may be required to access all resource tools.] This lesson applies the trigonometric ratios and their inverses to real-life situations.
Other
Algebra Lab: Word Lesson: Vectors Right Triangles Components and Resultants
Solve problems using vectors that involve velocity, speed, direction, and magnitude. Includes examples and practice problems. Click on the buttons under the practice questions to see the solutions.
Ministry of Education and Universities of the Region of Murcia (Spain)
Ministerio De Educacion Y Ciencia: Introduccion a La Trigonometria
This is an interactive activity introducing the concept of trigonometry and working with trigonometric functions to solve right triangles.
Texas Education Agency
Texas Gateway: Applying Pythagorean Triples to Solve Problems
Given verbal and pictorial representations of problem situations, the student will apply patterns from right triangles whose sides are Pythagorean Triples to solve the problems.
Other
Trig Without Tears: Solving Triangles
This page provides a good explanation of how to solve oblique triangles (triangles containing no right angles.) The Law of Cosines section is about halfway of the way down the page.
CK-12 Foundation
Ck 12: Algebra: Solving Equations Using the Pythagorean Theorem
[Free Registration/Login may be required to access all resource tools.] Use the Pythagorean Theorem to find a right triangle's missing side lengths.
Cuemath
Cuemath: Altitude of a Triangle
Explore the world of the altitude of a triangle in this mini-lesson including its definition, altitudes in different types of triangles, formulae, some solved examples, and a few interactive questions for you to test your understanding.