Curated Video
Finding Missing Angle Measures Using Simple Equations and the Triangle Sum Theorem
In this video tutorial, students are guided through the process of finding missing angle measures in triangles using simple equations and the triangle sum theorem. The teacher demonstrates step-by-step how to solve for the unknown angles...
Curated Video
Angles of Triangles and Similarity
In this video, the teacher reviews how to find angles in triangles using the triangle angle sum theorem. The teacher walks through four parts of a standardized math test question, showing step-by-step how to find missing angle...
Brian McLogan
Prove Sum of All Angles in a Triangle is 180 | Part 3
Lets write. a proof to show once and for all that the sum of all angles in a triangle is going to be 180 degrees. To do this I will use a two column proof.
Brian McLogan
Using the Angles of a Triangle to my Advantage | Part 4
Once we are familar with all the angles in a triangle adds up to 180 it is now time to try to problems that will come in handy. So for in this video that is exactly what we are going to do.00:00 Intro 00:24 Find the Value of x Using...
Brian McLogan
What is the Third Angle Theorem of Triangles
👉 Learn about congruent triangles theorems. Two or more triangles are said to be congruent if they have the same shape and size. There are many methods to determine whether two triangles are congruent. Some of the methods include: (1)...
Curated Video
Triangle Sum Theorem and Exterior Angle Theorem
In this video, the teacher explains the basics of triangles, including the interior and exterior angles. The lesson covers the triangle sum theorem, using ratios to find angle measures, and the exterior angle theorem. The teacher...
Curated Video
Find Corresponding Angles of Similar Triangles
In this short video we will answer a standardized math test question where we are asked to identify a missing angle of a triangle. We will review the definition and meaning of similar triangles. We will identify which angle corresponds...
Flipped Math
Unit 3 Review: Parallell and Perpendicular Lines
Learners watch a quick review on the Parallel and Perpendicular Lines unit. The pupils work through ten review problems ranging from identifying types of angles formed by parallel lines and transversals to writing equations of parallel...
Flipped Math
Parallel Lines and Triangles
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...
CK-12 Foundation
The Third Angle Theorem: Lesson
If two sets of angles are equal, the third set is too. An informative portion of a playlist on geometry develops the Third Angle Theorem for triangles. Using the theorem, the presenter shows how to determine the measure of missing angles...
CK-12 Foundation
Triangle Sum Theorem: Lesson
The measures all add up. The presentation, part of a helpful playlist on geometry, provides the statement of the Triangle Sum Theorem. Using the theorem, the video shows how to find the missing measure of an angle.
Mathed Up!
Angles: Parallel Lines
Viewers are presented with seven problems with parallel lines and angle relationships and must use the given information to find the measures of specific angles. To finish, they explain their process in finding the measures in the...
Brightstorm
Triangle Angle Sum
Don't believe everything that you hear — make them prove it! The video shows two methods to prove the Triangle Angle Sum Theorem. The following two videos apply the theorem to finding missing angle measures.
Curated OER
Why Are the Angles of Equilateral Triangles Always Equal to 60¼?
Learn how to identify an equilateral triangle by evaluating its congruent sides. Once you've determined that that sides are congruent you'll be able to use the triangle sum theorem to determine the angles in an equilateral triangle. This...
Curated OER
How Do You Find Missing Angles in a Triangle With Variables?
Are you working on finding the missing angles of triangles in your class? Consider this video. An instructor uses the triangle sum theorem to create an equation that helps her find the missing angles. She explains each step and writes...
Curated OER
What is a Triangle?
Triangles, triangles, triangles. What makes a polygon a triangle? How many types of triangles are there? How do you determine what kind of triangle it is? Watch this video as the teacher explains 'tri' meaning three, making a triangle -...
Curated OER
How Do You Find Missing Angles in a Triangle With Variables?
Are you working on finding the missing angles in triangles in your class? Consider this video. An instructor uses the triangle sum theorem to create an equation that helps her find the missing angles. She explains each step and writes...
Socratica
Sum of the Angles in a Triangle
You know that triangles have angle sums of 180 degrees, but can you prove it? A brief video in the Socratica Geometry series highlights an informal geometric proof. It shows that the sum of the interior angles of a triangle is 180...
Curated OER
How Do You Find the Angles in a Triangle if You Have a Ratio of Their Measures?
Use the Triangle Sum Theorem to find the value of each of the inside angles of a triangle. This triangle problem has to do with the ratio of the angles to each other. Find the measure of each angle if the ratio is 1:3:8. Not sure how to...
Curated OER
How Do You Find a Missing Angle in a Right Triangle?
The triangle sum theorem states that the interior angles of a triangle add up to 180 degrees. So it seems logical that if there are two known values given for the interior angles of a triangle, the third value could be found using this...
Curated OER
How Do You Find Missing Angles in an Isosceles Triangle Using Right Triangles?
Given an isosceles triangle, and the value of one angle, find the missing values. There are some special properties about isosceles triangles. Use the triangle sum theorem to solve this problem. Watch this video to see how the instructor...
Curated OER
How Do You Find Missing Angles in an Isosceles Triangle?
Finding the missing values of two angles in an isosceles triangle is not as difficult as it sounds. But how can two out of three angle's measurements be found? Well, there are special properties about an isosceles triangle which make...
Curated OER
How Do You Find a Missing Angle in a Triangle?
The interior angles of any and ALL triangles adds up to 180 degrees. So if given two of the angle degrees, is it possible to find the value of the third angle? Yes! Use the triangle sum theorem to solve for the missing angle. Watch this...
Virtual Nerd
What is the Triangle Sum Theorem?
If you add the value of the three interior angles in a triangle will it equal 180 degrees? Yes it will. The instructor illustrates and proves the Triangle Sum Theorem. Follow closely as she explains her proof.