



Now... gain access to over 2 Million curated educational videos and 500,000 educator reviews to free & open educational resources
We found 44 resources with the concept obtuse triangles
Videos (Over 2 Million Educational Videos Available)

4:59
Biography of Mary Cassatt for Kids: Famous...
10:23
Algebra 50 - Three Variable Systems in the...
3:11
Defining Gravity
Other Resource Types ( 44 )
EngageNY
EngageNY Precalculus and Advanced Topics Curriculum
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...
Lesson Planet
Math Antics Geometry Video Lessons
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
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
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
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...
Lesson Planet
Can You Solve the Unstoppable Blob Riddle?
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
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
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
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...
Lesson Planet
Applications of the Pythagorean Theorem: Lesson
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....
Lesson Planet
Altitudes: Examples
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?
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.
Lesson Planet
Classifying Triangles: Lesson
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
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
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....
Lesson Planet
Triangles
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
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.
EngageNY
The Area of All Triangles Using Height and Base
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
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?
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...
EngageNY
An Area Formula for Triangles
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
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...
Lesson Planet
Pythagorean Inequalities
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
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.