Refine Your Results

Content Curators

Grades

Subjects

Resource Types

Standards

Now... gain access to over 2 Million curated educational videos and 500,000 educator reviews to free & open educational resources

Get a 10 Day Free Trial

44 resources with the concept obtuse triangles

Videos (Over 2 Million Educational Videos Available)
Biography of Mary Cassatt for Kids: Famous Artists for Children - FreeSchool Video
4:59
Biography of Mary Cassatt for Kids: Famous...
Algebra 50 - Three Variable Systems in the Real World - Problem 2 Video
10:23
Algebra 50 - Three Variable Systems in the...
Defining Gravity Video
3:11
Defining Gravity
Other Resource Types ( 44 )
EngageNY

EngageNY Precalculus and Advanced Topics Curriculum

For Teachers 11th - 12th Standards
A 5-module complete precalculus course begins with young mathematicians exploring linearity, complex number operations as transformation, and the power of the right notation. Module 2 has pupils examining incidence relationships in...
12 Items in Collection
Lesson Planet

Math Antics Geometry Video Lessons

For Teachers 4th - 8th Standards
The point of this collection of 12 videos is to introduce learners to three basic parts of geometry—points, lines, and planes. The presenter provides definitions, shows how to classify shapes, provides examples, and shows how to use...
EngageNY

EngageNY Precalculus and Advanced Topics Module 4: Trigonometry

For Teachers 11th - 12th Standards
Introduce advanced math students to the power of trigonometry! The 14 lessons in the Module 4 collection are divided into three topics: Trigonometric Functions, Trigonometry and Triangles, and Inverse Trigonometric Functions. Each lesson...
Lesson Planet

Study Jams! Classify Triangles

For Students 5th - 8th Standards
Jam on with this multi-faceted activity teaching triangle classification. Start with a learner-paced lesson describing the different qualities of triangles and follow with a fun karaoke session. Also provided are two types of...
Lesson Planet

Colorful Triangles

For Students 4th - 5th Standards
Learners examine a figure made up of different types of triangles and then determine whether each triangle is right, acute, or obtuse. Next, they color each type of triangle a different color. Finally, pupils answer three fill in the...
3:42
Lesson Planet

Can You Solve the Unstoppable Blob Riddle?

For Students 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.
Lesson Planet

Terrific Triangles

For Teachers 4th - 6th Standards
Scholars show what they know about types of triangles with a hands-on activity that challenges them to build models using toothpicks. Following a whole-class discussion and brief presentation, small groups gather to form shapes and...
Lesson Planet

Accessible Shapes

For Teachers 6th - 8th Standards
All the 2-D and 3-D measurement work you need is in one location. Divided into three sections, the geometry lesson plans consist of visualization of three dimensions, classifying geometric figures, and finding surface area and volume....
Lesson Planet

Always, Sometimes, Never

For Students 9th - 10th Standards
Do your learners always, sometimes, or never remember the properties of the segments in triangles? Get that number closer to always with a creative lesson analyzing all four segments. Scholars consider a statement about one of the...
3:34
Lesson Planet

Applications of the Pythagorean Theorem: Lesson

For Students 8th - 11th Standards
The Pythagorean Theorem works for something other than right triangles; show your class all it can do. Using information from the Pythagorean Theorem, the video shows how to determine whether a triangle is an acute or obtuse triangle....
3:45
Lesson Planet

Altitudes: Examples

For Students 6th - 11th Standards
Find the location of altitudes—from any elevation! The video presents the definition of an altitude of a triangle. By drawing examples, the segment of a larger geometry playlist highlights the location of altitudes of various triangle...
Lesson Planet

What You Know About the Bermuda Triangle?

For Teachers 9th - 12th Standards
Get lost in the classifications. Using the backdrop of the Bermuda Triangle, pupils classify it by angle and side measures. They also learn information about the triangle and its history.
4:55
Lesson Planet

Classifying Triangles: Lesson

For Students 4th - 8th Standards
That's correct, it is right and scalene. The video introduces the two methods for classifying triangles, sides, and angles. A resource in the playlist for basic geometry provides the definitions for each of the classifications.
Lesson Planet

Triangle Classification

For Teachers 9th - 12th Standards
Oh triangle, where are the points that will make your type? Given a line segment, pairs determine the location of a third point to create the six different types of triangles. The teacher provides a jumping off point by leading a...
Lesson Planet

Discovering Triangle Sum

For Teachers 8th - 10th Standards
Math is everywhere, even in bikes! Groups investigate the sum of the angles of a triangles with two method—measurements and transformations. Using diagrams of bicycles, classmates find the types of triangles formed by the seat and axles....
1 In 1 Collection 7:40
Lesson Planet

Triangles

For Students 4th - 8th Standards
What has three sides and is adorable? A-cute triangle. The resource introduces triangles and how to classify them by sides and angles or both. The video concludes with using the sum of the angles of a triangle to show how to solve for a...
Lesson Planet

Ambiguous Case: Furniture Store Problems

For Students 10th - 12th
Remove any ambiguity about using a helpful resource. Individuals use an interactive to find the number of triangles that fit given conditions. They find that some conditions can result in more than one triangle in the ambiguous case.
1 In 1 Collection
EngageNY

The Area of All Triangles Using Height and Base

For Teachers 6th Standards
Drop in the altitude is all that is needed. Pupils explore finding areas of different types of triangles. Learners realize the formula for finding their area is the same and explore the location of altitudes in triangles to finish the...
Lesson Planet

Pythagorean Theorem to Classify Triangles: Missing Angles

For Students 8th - 12th Standards
Learn to use the Pythagorean Theorem with non-right triangles. Pupils use the interactive to discover the relationship between the lengths of sides for acute and obtuse triangles. They compare the squares of the sides of the triangles to...
Lesson Planet

How Many Triangles?

For Teachers 9th - 11th Standards
Something for young mathematicians to remember: the sum of any two sides must be greater than the third. Class members investigates the Triangle Inequality Theorem to find the relationship between the sides of a triangle. At the same...
2 In 2 Collections
EngageNY

An Area Formula for Triangles

For Teachers 11th - 12th Standards
Use a triangle area formula that works when the height is unknown. The eighth installment in a 16-part series on trigonometry revisits the trigonometric triangle area formula that previously was shown to work with the acute triangles....
Lesson Planet

Rods and Triangles

For Teachers 6th - 9th
Scholars explore triangles with rods of different lengths. Using rods of 2, 4, 6, 8, and 10 cm class members build as many different types of triangles as they can. They also describe properties of these triangles and determine...
5:14
Lesson Planet

Pythagorean Inequalities

For Students 9th - 12th Standards
Right, acute, or obtuse: how do you know? Learners observe how to use the Pythagorean Theorem to determine the type of triangle from a set of side lengths. The video includes an example of each triangle type.
Lesson Planet

Common Geometric Figures

For Students 8th - 11th Standards
Geometry could be called the study of figures. An overview of the figures found in a typical geometry course contains a study of different triangles, quadrilaterals, and regular polygons.