Instructional Video
Khan Academy

Khan Academy: Triangles: 45 45 90 Triangle Side Ratios

9th - 10th
Showing the ratios of the sides of a 45-45-90 triangle in this short video.
Instructional Video
Khan Academy

Khan Academy: Triangles: 30 60 90 Triangle Side Ratios Proof

9th - 10th
This video explores proving the ratios between the sides of a 30-60-90 triangle.
Instructional Video
Khan Academy

Khan Academy: Triangles: 45 45 90 Triangles

9th - 10th
Students are provided an introduction to 45-45-90 triangles by watching a video tutorial.
Instructional Video
Khan Academy

Khan Academy: Worked Examples: Geometry: Pythagorean Theorem, Area

9th - 10th Standards
Students watch a video tutorial to learn how to solve area problems of composite figures using the Pythagorean Theorem.
Instructional Video
Khan Academy

Khan Academy: Trig to Solve the Sides and Angles of a Right Triangle

9th - 10th Standards
Worked example using trigonometry to solve for the lengths of the sides of a right triangle given one of the non-right angles.
Instructional Video
Khan Academy

Khan Academy: Triangles: Another Pythagorean Theorem Proof

9th - 10th Standards
Students explore the Pythagorean Theorem by exploring a visual proof of the Theorem as they watch a video tutorial.
Instructional Video
Sophia Learning

Sophia: Calculating the Area of a Triangle

9th - 10th Standards
This video lesson demonstrates how to calculate the area of a triangle. It includes detailed examples including ones that use the Pythagorean Theorem. Students can check their understanding with an assessment. [10:43]
Instructional Video
Sophia Learning

Sophia: Identifying Trigonometric Ratios From a Right Triangle

9th - 10th Standards
Use a right triangle to identify the six trigonometric ratios such as cosine, sine, tangent, co-secant, secant, and cotangent. Assess learning with a quiz. [6:54]
Instructional Video
Sophia Learning

Sophia: Inverse Cosine

9th - 10th
Solve for an unknown angle of a right triangle using the inverse cosine. Assess learning with a quiz.
Instructional Video
Sophia Learning

Sophia: Inverse Tangent

9th - 10th
Solve for an unknown angle of a right triangle using the inverse tangent. Take a quiz to assess learning.
Instructional Video
Sophia Learning

Sophia: Rectangle Practice Problems

9th - 10th
This video lesson describes the characteristics of rectangles and provides examples of how to find area, perimeter, diagonals, and angle measurements. [7:00]
Instructional Video
Sophia Learning

Sophia: Slant Height of a Cone

9th - 10th
This video lesson demonstrates how to find the slant height of a right cone. Students can check their understanding with an assessment. [6:18]
Instructional Video
Sophia Learning

Sophia: Slant Height of a Pyramid

9th - 10th
This video lesson demonstrates how to use the Pythagorean Theorem to find the slant height of pyramid.
Instructional Video
Sophia Learning

Sophia: The Hypotenuse

9th - 10th
In this video tutorial, the instructor defines and explores the hypotenuse of a right triangle. Students can check their understanding with a quiz. [1:35]
Instructional Video
Sophia Learning

Sophia: Area of a Rhombus

9th - 10th
This video lesson demonstrates two ways for calculating the area of a rhombus. Students can check their understanding with an assessment. [4:55]
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.