## Reflection: Diverse Entry Points Argument for the Volume Formula of a Cylinder - Section 2: Reasoning from Rectangular Prisms to Triangular Prisms

The paragraph after item #5 reads,

Therefore, we can conclude that the volume of our original triangular prism, is the sum of half the volumes of the prisms with ADBD and FBEC as their bases. Another way to say this is that the volume of our original triangular prism is half the sum of the volumes of the prisms with ADBD and FBEC as their bases. That means the volume of our original triangular prism is half the volume of the rectangular prism from which it was “sculpted”.

I can understand if this is gibberish to my students. So when I see their eyes glazing over as they read it, I know I need to break it down by relating the words to the diagram and translating all the words in to more concise math notation. This is the skill of digesting dense math text and it's a skill my students need to be taught.

Breaking it down when the text gets too wordy
Diverse Entry Points: Breaking it down when the text gets too wordy

# Argument for the Volume Formula of a Cylinder

Unit 11: Measurement and Dimension
Lesson 3 of 6

## Big Idea: Why don't they just call them circular prisms? In this lesson, students use their knowledge of prisms to reason about the volume formula for cylinders.

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75 minutes

### Anthony Carruthers

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