Reflection: Students with Disabilities Proving Parallelograms - Section 2: Vocabulary and Exploration 1


In the practice problems for this section of notes, I led my students through the first example and modeled how to complete this problem.   Since we needed to use the first angle measure we found to find the next, I discussed with the class how to "mark-up" our polygon.  You can see in this example, Visualizing Math, that I specifically used blue to find the first angle A, and then wrote this angle inside the parallelogram.  Once we had this angle written in, it was easy for my students to see that the angle across, angle C, also had to be 72 degrees.  As we plugged in the values for x and y, we predicted the measure of each angle, and used this to justify each step. 

  Students with Disabilities: Visualizing Angles and Sides
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Proving Parallelograms

Unit 6: Pretty Polygons
Lesson 4 of 8

Objective: SWBAT prove that quadrilaterals are parallelograms using the definition of parallelogram and six key parallelogram property theorems.

Big Idea: Two pair-share proofs await to challenge students in this lesson on proving that quadrilaterals are parallelograms.

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parallelogram proving parallelogram images
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