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Classifying Triangles

Classifying Triangles


At the end of this lesson, students will be able to classify triangles by their sides and angles, with 90% accuracy. using mathematical terms, and reasoning to support their thinking.

This lesson is all about triangles and how they can be classified by their side lengths, and angles. Remember to take notes on your corresponding homework paper, and use those notes as a resource to answer the questions at the bottom of the page. 


While watching the video, keep the following in mind:

acute angle - an angle that is smaller than 90°

obtuse angle - an angle that is greater than 90°

right angle - an angle that measures exactly 90°, and is created by intersecting line segments


Record one or two questions or thoughts that you have during the video to discuss in class.

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Learn how to classify triangles by the length of their sides and the size of their angles!

Source: Created by Jaqulyn Bartomioli using Explain Everything for iPad


Prove what you know! Use the information in the slideshow to answer the questions below. Feel free to go back and use your resources!

Source: Created by Jaqulyn Bartomioli using Google Forms