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373 resources with the keyterm triangle

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Other Resource Types (373)
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Lesson Planet

Two Triangles' Area

For Teachers 7th - 9th Standards
Need an activity for teaching the Pythagorean Theorem? Geometry juniors apply the Pythagorean theorem to two triangles to determine a final calculation. 
Lesson Planet

Triangle's Interior Angles

For Teachers 7th - 9th Standards
Given a pair of parallel lines and a triangle in between, geometers prove that the sum of the interior angles is 180 degrees. This quick quest can be used as a pop quiz or exit ticket for your geometry class.
Lesson Planet

Triangles

For Teachers 5th - 6th
In this math worksheet, students answer 3 questions about an equilateral triangle. Students then answer 3 questions about isosceles triangles. Students then calculate missing angles on isosceles triangles.
Lesson Planet

Writing Task 6.G.3 Item 2

For Students 5th - 6th Standards
Donnie and Steward each created triangles on a coordinate plane and want to know if they have the same area. Young mathematicians use their ability to plot ordered pairs and find the area of triangles to help answer this...
Lesson Planet

All vs. Only Some

For Teachers Pre-K - 2nd Standards
All shapes have certain defining attributes that set them apart from others. In order to understand this, young mathematicians look at examples and non-examples of triangles, rectangles, and squares, working as a whole class to create...
Lesson Planet

Alike or Different Game

For Teachers K Standards
How are a circle and triangle alike? How are they different? These are the types of questions children will answer while playing this fun geometry game. Including a variety of conventional and unconventional shapes, this activity allows...
Lesson Planet

Study Jams! Area of a Triangle

For Students 4th - 6th Standards
Even though there is a wide variety of different triangles in the world, knowing a single equation allows us to find the area of each and every one of them. Follow along with this step-by-step presentation as Zoe clearly models how to...
Lesson Planet

Grandfather Tang's Story

For Teachers K - 2nd Standards
It's amazing the complex figures that can be made using only a few simple shapes. Following a class reading of the children's book Grandfather Tang's Story by Ann Tompert, young mathematicians use sets of tangrams to create models of the...
7:43
Lesson Planet

What is the Formula for the Volume of a Prism?

For Teachers 6th - 10th
Is prism just another mathematical term for a solid? It must be since this lesson is about volume. The teacher illustrates and explains how to find the volume of a rectangular prism and also how to find the volume of a triangular prism....
2:47
Lesson Planet

How Do You Find the Sine of an Angle in a Right Triangle?

For Teachers 7th - 11th
A trigonometric ratio is a ratio between two sides of a right triangle. In this problem, find sin(A) in the given right triangle. Use the ratio of the opposite side over the hypotenuse.
2:12
Lesson Planet

What are the Legs and Hypotenuse of a Right Triangle?

For Teachers 6th - 10th
What are all the parts of a right triangle called? What makes it a right triangle? Legs? Triangles have legs? Hypotenuse? Pythagorean Theorem? The instructor diagrams and identifies all the parts of a right triangle for you.
5:56
Lesson Planet

How Do You Find the Volume of a Triangular Pyramid?

For Teachers 6th - 10th
Instruct your class on how to find the volume of a triangular pyramid using this tutorial. Learners can watch the video and take notes, later applying what they have seen to class work or homework. A clear video with direct instruction,...
3:34
Lesson Planet

How Do You Find the Area of a Triangle?

For Teachers 6th - 8th
The formula for the area of a triangle is: area equals one half the base times the height. If you have been given these two values then all you need to do is plug them into the formula and solve. Don't forget to write the correct ending...
5:09
Lesson Planet

How Do You Find Missing Angles in a Triangle With Variables?

For Teachers 8th - 10th
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...
5:58
Lesson Planet

What is a Triangle?

For Teachers 1st - 5th
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 -...
2:49
Lesson Planet

How Do You Determine if a Triangle Is a Right Triangle if You Know its Sides?

For Teachers 6th - 10th
Use the Pythagorean Theorem formula to check if this given triangle, with the given lengths of each side, is a right triangle. It's as simple as plugging the given values into the formula and doing the math to see if the solution checks...
1:40
Lesson Planet

Hypotenuse

For Teachers 5th - 8th
Entertain your students with this fun video where students explain how to solve for the hypotenuse. They are clearly enjoying themselves while they explain how to use the Pythagorean theorem.
2:59
Lesson Planet

Determining Whether a Group of Sides Can Form a Triangle

For Teachers 5th - 8th
How do you know if three given lengths of lines can form a triangle? This lesson will give you two rules to help you determine if you can make a triangle.
2:35
Lesson Planet

Determining the Angle of Elevation Using Tangent

For Teachers 10th - 12th
What's the angle of elevation? Using several tangent formulas, the instructor calculates the angle of elevation. He has two examples that are engaging.
3:36
Lesson Planet

Area of a Triangle - Geometry Help

For Teachers 4th - 7th
Do you know what A=1/2 bh means? If you don't this video on the area of a triangle is a must. It defines the formula needed to determine the area of a triangle, works through an example problem, and clearly explains the procedure.
4:22
Lesson Planet

How Do You Solve a Problem Using Indirect Measurement with Shadows?

For Teachers 6th - 10th
Using indirect measurement, this video shows viewers how to find the height of a flagpole. The lecturer employs drawings as well as proportions to solve this problem, explaining each step. A useful resource to aid struggling learners and...
Lesson Planet

Section 2.5 - Problem Solving (Part B)

For Students 7th - 12th
Trying to figure out the perimeter of a geometric figure? Here are a few word problems to set up algebraic equations to solve for perimeter. There are also some word problems to set up algebraic equations to solve for angles in a...
6:31
Lesson Planet

How Do You Find the Volume of a Triangular Pyramid?

For Teachers 6th - 12th
Instruct your class on how to find the volume of a triangular pyramid using this tutorial. Learners can watch the video and take notes, later applying what they have seen to class work or homework. A clear video with direct instruction,...
5:44
Lesson Planet

How Do You Find Missing Angles in a Triangle With Variables?

For Teachers 6th - 12th
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...