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How Many Triangles Can You Make? (Given Conditions)
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What you will learn from this videoWhat you will learn
- We’ll learn that when you are given certain side lengths and angles of triangles, you can either form 1 triangle, no triangle, or many triangles!
- We will also learn that the 3 angles in a triangle add up to 180 degrees.
- And we'll see that this knowledge can help us make jewelry, design clothes, and even work on spacecraft!
- Discussion Questions
Before Video
What is the name of a three-sided polygon?ANSWERA triangle.
Three sides, three angles. Three sides, three corners or vertices.
In degrees.
Right, acute, obtuse, isosceles, scalene, equilateral.
A triangle in which all three sides are the same length.
After Video
What is the sum of the three angles of a triangle?ANSWER180 degrees.
The length of two sides combined must be greater than the third side. Example: 2 cm, 3 cm, 4 cm
The lengths of two sides combined must be less than the third side. Example: 2 in., 2 in., 5 in.
Many triangles (an infinite number of triangles)
No triangles; the angles do not add to 180 degrees.
- Vocabulary
- Triangle DEFINE
A three-sided polygon.
- Angle DEFINE
A figure formed by two rays or two line segments with a common endpoint called the vertex of the angle.
- Ray DEFINE
A part of a line starting at an endpoint and continuing forever in one direction.
- Vertex DEFINE
The point at which the rays of an angle meet.
- Scale DEFINE
The relative size of something. It is the same as a scale factor.
- Protractor DEFINE
A tool used for measuring or drawing angles.
- Triangle DEFINE
- Reading Material
- Practice Word Problems
- Practice Number Problems
- Lesson Plan
- Teacher Guide
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