Instructional Video
Sophia Learning

Sophia: Pythagorean Theorem Proof

9th - 10th Standards
Find the area of several figures to prove the Pythagorean theorem. Complete quiz to check understanding. [5:16]
Instructional Video
Khan Academy

Khan Academy: Example: Unit Circle Definition to Calculate Sin and Cos

9th - 10th Standards
Explains how to use the unit circle definition to calculate sin and cos of multiple angles. [15:26]
Instructional Video
Virtual Nerd

Virtual Nerd: How Do You Find a Missing Angle in a Right Triangle?

9th - 10th
It's important to first identify what type of triangle you're working with before trying to solve for a missing interior angle measurement. Learn how by watching this tutorial. [3:34]
Instructional Video
Virtual Nerd

Virtual Nerd: Determine if a Triangle Is a Right Triangle if You Know Its Sides

9th - 10th Standards
Take a look at this tutorial and learn how to use the Pythagorean theorem to see if a triangle is a right triangle. [2:49]
Instructional Video
Imagine Learning Classroom

Learn Zillion: Lesson Video for 'Create a Right Triangle on a Coordinate Plane'

8th Standards
In this lesson, you will learn how to create a right triangle on a coordinate plane by using two points that form a diagonal line segment. [4:39]
Instructional Video
Virtual Nerd

Virtual Nerd: How Do You Find a Missing Hypotenuse in a 45 45 90 Triangle?

9th - 10th Standards
In this tutorial, see how to solve for a missing side length by using your knowledge of 45-45-90 triangles to find a scale factor and set up an equation to solve. [4:51]
Instructional Video
Math Antics

Math Antics: The Pythagorean Theorem

5th - 9th Standards
Gain a basic understanding of the Pythagorean Theorem by watching this easy to understand video tutorial. Additional resources are available as part of a paid subscription service. [12:55]
Instructional Video
Khan Academy

Khan Academy: Triangles: Circumcenter of a Right Triangle

9th - 10th Standards
The video tutorial shows that the midpoint of the hypotenuse is the circumcenter.
Instructional Video
Loyola University Chicago

Math Flix: Pythagorean Theorem Equation Practice

3rd - 8th
This QuickTime movie provides an excellent opportunity to apply the Pythagorean Theorem to several right triangles. As you watch and listen to the teacher and student interact it helps clarify the thinking behind applying this concept.
Instructional Video
Virtual Nerd

Virtual Nerd: How Do You Find the Sine of an Angle in a Right Triangle?

9th - 10th Standards
A trigonometric ratio is a ratio between two sides of a right triangle and includes the sine ratio. Discover how to find the sine of a particular angle in a right triangle by watching this video. [2:48]
Instructional Video
Virtual Nerd

Virtual Nerd: How Do You Find the Cosine of an Angle in a Right Triangle?

9th - 10th Standards
A trigonometric ratio is a ratio between two sides of a right triangle. The cosine ratio is one of these ratios. Take a look at this tutorial to see how to find the cosine of a particular angle in a right triangle. [3:22]
Instructional Video
Khan Academy

Khan Academy: Right Triangle Geometry Harder Example

9th - 10th
The video from Khan Academy provides practice questions for the SAT. Students will watch Sal work through a harder right triangle trigonometry problem.
Instructional Video
Khan Academy

Khan Academy: Right Triangle Geometry Basic Example

9th - 10th
The video from Khan Academy provides practice questions for the SAT. Students will watch Sal work through a basic right triangle trigonometry problem.
Instructional Video
Khan Academy

Khan Academy: Right Triangle Word Problems Harder Example

9th - 10th
The video from Khan Academy provides practice questions for the SAT. Students will watch Sal work through a right triangle word problem that is more challenging than other examples that are available.
Instructional Video
Khan Academy

Khan Academy: Right Triangle Word Problems Basic Example

9th - 10th
The video from Khan Academy provides practice questions for the SAT. Students will watch Sal work through a basic Right triangle word problem.
Instructional Video
Sophia Learning

Sophia: Drawing a Triangle on the Unit Circle: Lesson 2

9th - 10th Standards
This lesson shows how to draw a right triangle on a unit circle. It is 2 of 7 in the series titled "Drawing a Triangle on the Unit Circle."
Instructional Video
Sophia Learning

Sophia: Drawing a Triangle on the Unit Circle: Lesson 4

9th - 10th Standards
This lesson shows how to draw a right triangle on a unit circle. It is 4 of 7 in the series titled "Drawing a Triangle on the Unit Circle."
Instructional Video
Sophia Learning

Sophia: Drawing a Triangle on the Unit Circle: Lesson 5

9th - 10th Standards
This lesson shows how to draw a right triangle on a unit circle. It is 5 of 7 in the series titled "Drawing a Triangle on the Unit Circle."
Instructional Video
Sophia Learning

Sophia: Drawing a Triangle on the Unit Circle: Lesson 6

9th - 10th Standards
This lesson shows how to draw a right triangle on a unit circle. It is 6 of 7 in the series titled "Drawing a Triangle on the Unit Circle."
Instructional Video
Sophia Learning

Sophia: Drawing a Triangle on the Unit Circle: Lesson 7

9th - 10th
This lesson shows how to draw a right triangle on a unit circle. It is 7 of 7 in the series titled "Drawing a Triangle on the Unit Circle."
Instructional Video
Sophia Learning

Sophia: Drawing a Triangle on the Unit Circle: Lesson 1

9th - 10th Standards
This lesson shows how to draw a right triangle on a unit circle. It is 1 of 7 in the series titled "Drawing a Triangle on the Unit Circle."
Instructional Video
Sophia Learning

Sophia: Finding the Missing Angle of Right Triangle: Lesson 2

9th - 10th
Following this lesson, the angle measure of one non-right angle of a right triangle, and the right angle symbol in the right angle of the triangle, you'll be able to determine the value of the missing angle. It is 2 of 9 in the series...
Instructional Video
Sophia Learning

Sophia: Finding the Missing Angle of Right Triangle: Lesson 6

9th - 10th
Following this lesson, the angle measure of one non-right angle of a right triangle, and the right angle symbol in the right angle of the triangle, you'll be able to determine the value of the missing angle. It is 6 of 9 in the series...
Instructional Video
Sophia Learning

Sophia: Finding the Missing Side of a 45 45 90 Triangle: Lesson 9

9th - 10th
In this lesson, you'll learn how to use the lengths of two sides of a triangle and the ratio of the side lengths to find the length of the missing side. It is 9 of 9 in the series titled "Finding the Missing Side of a 45-45-90 Triangle."