Instructional Video9:25
Khan Academy

SAT Prep: Test 5 Section 9 Part 1

9th - 12th
Reasoning through the methodology of a new set of problems from page 679 of The Official SAT Study Guide, Sal shows students how to find the ins and outs of increasingly difficult math problems. He advises them to thoroughly think over...
Instructional Video1:46
Curated OER

Telly Plays The Triangle

Pre-K - K
Big Bird gives Telly a lesson on living vs. non-living things in this film. Telly is afraid to play a musical instrument, a triangle, he is holding because he thinks he might hurt it. After Big Bird tells Telly the triangle isn't living,...
Instructional Video
Khan Academy

SAT Prep: Test 3 Section 2 Part 4

9th - 12th
Finding perimeters and slopes is the focus of this video, which details ways to solve problems 15-17 on the practice SAT. Even students who are confident in their ability to pass the SAT would benefit from this additional review.
Instructional Video13:09
2
2
Flipped Math

AAS and ASA

9th - 12th Standards
Sometimes one knows more about angles than about sides. Young mathematicians learn about the AAS and ASA triangle congruence criteria by watching an informative video. They use these shortcuts to demonstrate triangle congruence in...
Instructional Video10:08
2
2
Flipped Math

Unit 4 Review: Triangle Congruence

9th - 12th Standards
It's time to prove one's knowledge of triangle congruence proofs. Scholars watch a video to review triangle classifications and how to use properties of triangles to set up and solve equations for missing values. They also review the...
Instructional Video11:32
2
2
Flipped Math

CPCTC and HL Theorem

9th - 12th Standards
The resource is sure to be a right fit for introducing the congruence of right triangles. The fourth of five lessons in the Geometry - Triangle Congruence unit teaches pupils how to use CPCTC to prove congruent parts. They also apply the...
Instructional Video15:16
2
2
Flipped Math

SSS and SAS

9th - 12th Standards
Why use six corresponding parts when three will suffice? The second of five lessons in the Geometry - Triangle Congruence unit focuses on the SSS and SAS triangle congruence criteria. By watching a video, scholars learn how to identify...
Instructional Video14:49
2
2
Flipped Math

Triangles

9th - 12th Standards
Take time to tackle triangles. Scholars watch a video that first reviews the types of triangles. They then investigate the Isosceles Triangle Theorem and see how to apply it to solve problems. At the end, individuals also learn how to...
Instructional Video14:37
2
2
Flipped Math

Parallel Lines and Triangles

9th - 12th Standards
Triangles bring sums to geometry. The lesson presents two theorems dealing with the angles of a triangle. Pupils learn about the Triangle Sum Theorem and the Exterior Angle Theorem, and then apply the theorems to create equations and...
Instructional Video3:42
TED-Ed

Can You Solve the Unstoppable Blob Riddle?

6th - Higher Ed Standards
Viewers of an entertaining short video have an opportunity to save the world! All they have to do is solve the unstoppable blob riddle. Acute learners will have no problem with this problem.
Instructional Video3:08
Corbett Maths

Constructing SSS Triangles

8th - 11th Standards
Creating a triangles is as easy as 5, 6, 7. Using a ruler and compass to measure off lengths, a short video shows how to construct a triangle with three specific side lengths. The example creates a triangle with side lengths of 5 cm, 6...
Instructional Video1:47
Corbett Maths

Constructing SAS Triangles

8th - 11th Standards
Two sides and an angle ... a triangle it makes. Given the measure to two sides and the angle between them, the narrator of a short video shows how to draw a triangle with a ruler and protractor. Pupils use handouts to practice the newly...
Instructional Video2:22
Corbett Maths

Constructing ASA Triangles

8th - 11th Standards
The narrator of a short video explains the steps in constructing a triangle given the measure of two angles and the length of the side between the angles. The resource provides opportunities for pupils to practice the skill with two...
Instructional Video5:39
SciShow

How Can the Universe Be Flat?

9th - Higher Ed Standards
Flat, positively curved, or negatively curved ... what is the true shape of the universe? Scientists use many indirect measurements to base their theories on the shape of the universe. Using an installment from the SciShow Space series,...
Instructional Video9:09
Corbett Maths

Congruent Triangles

6th - 12th Standards
Young mathematicians learn about the many theorems related to congruent triangles. The video allows them to stop and replay the content as many times as needed to take notes. Extra practice problems work as reinforcement for each skill...
Instructional Video2:31
Corbett Maths

Angle in a Semi-Circle – Proof

6th - 12th Standards
Young mathematicians observe a geometric proof using a short video. They see each part of the diagram clearly labeled and the simple math written off to the side. The new knowledge helps them solve additional problems independently.
Instructional Video3:50
Corbett Maths

Area of a Triangle

6th - 8th Standards
Base times height or one half base times height ... area formulas are pretty predictable! Given the base and height dimensions of a triangle, a video lesson explains the process of finding the area. Learners have the opportunity to...
Instructional Video2:48
Mathispower4u

Find the Base of a Triangle Given Area

7th - 10th Standards
Base a lesson on an informative video perfect for expanding your class's knowledge of triangles. Young mathematicians watch a brief YouTube video that teaches how to solve for the base of a triangle given its height and area. It also...
Instructional Video3:13
CK-12 Foundation

Area and Perimeter of Triangles: Lesson

6th - 10th Standards
Go from a parallelogram to a triangle. A segment of an extensive playlist on basic geometry shows the derivation of the formula for the area of a triangle. The resource works examples that require finding a missing side or height to...
Instructional Video2:07
CK-12 Foundation

SSS Similarity Theorem: Lesson

9th - 11th Standards
Judging by the sides, things appear similar. A portion of a larger playlist on geometry introduces the Side-Side-Side Similarity Theorem. The video shows how to use the lengths of sides to determine whether triangles are similar.
Instructional Video6:07
CK-12 Foundation

Medians: Examples

8th - 11th Standards
Balance the knowledge of intersecting medians. Using examples, the portion of a geometry playlist introduces the centroid. A video describes the property of the location of the triangle medians' point of concurrency. 
Instructional Video3:07
CK-12 Foundation

Perpendicular Bisectors: Lesson

8th - 11th Standards
Get right up and split it in half. Using a diagram, the video provides the definition of a perpendicular bisector. The portion in a playlist on basic geometry explains perpendicular bisector of a segment and of triangle sides properties.
Instructional Video2:35
CK-12 Foundation

Triangle AA Similarity: Lesson

7th - 11th Standards
Two sets of congruent angles leads to three. Using diagrams of two triangles, the presentation intuitively shows that if two sets of angles are congruent, the third set is too. The portion of a geometry playlist uses that information to...
Instructional Video5:25
CK-12 Foundation

Comparing Triangle Angles and Sides: Lesson

7th - 11th
Use the opposite to organize angles or sides. The video provides the relationship of angle measures based on the lengths of sides in a triangle and its converse. Using two triangles, the segment of a larger playlist on geometry shows the...