Classifying Triangles
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Objective
I can classify triangles by their angles and sides.
Part 1 of 4
Warm-up video
mathantics · 7:40Vetted channel
We don't generate video — this one is by mathantics on YouTube. The practice questions and exit ticket below were drafted by AI for this objective, and every question is editable in the teacher guide.
Part 2 of 4
Key concepts
3 concepts
- 1
Triangles are polygons that always have 3 sides and 3 angles.
- 2
Triangles can be classified by their sides (equilateral, isosceles, and scalene) and by their angles (right, acute, and obtuse).
- 3
The three angle measurements of any triangle, when combined, will always add up to 180 degrees.
Part 3 of 4
Practice
9 questions
What are the two main ways to classify triangles?
Explain the difference between an acute, right, and obtuse triangle.
Part 4 of 4
Exit ticket
Quick comprehension check
“Draw an example of an obtuse scalene triangle. Label the obtuse angle and indicate which sides, if any, are congruent.”
Sample answer included in the free materials
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Teacher guide, student handout, and slides — free, in Google Docs format
Teacher Guide
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