# ALEX Classroom Resource

## Geometry Module 3, Topic A: Area

Classroom Resource Information

Title:

Geometry Module 3, Topic A: Area

URL:

https://www.engageny.org/resource/geometry-module-3-topic-a-overview

Content Source:

EngageNY
Type: Lesson/Unit Plan

Overview:

In this topic, Lesson 1 shows how finding the area of a curved figure can be approximated by rectangles and triangles. By refining the size of the rectangles and triangles, the approximation of the area becomes closer to the actual area. Students experience a similar process of approximation to estimate in Grade 8, Module 7, Lesson 14. The informal limit argument prepares students for the development of volume formulas for cylinders and cones and foreshadows ideas that students formally explore in calculus. This process of approximation is important to developing the volume formula of cylinders and cones. In Lesson 2, students study the basic properties of the area using set notation; Topic B will examine how the properties are analogous to those of volume.

Content Standard(s):
 Mathematics MA2015 (2016) Grade: 9-12 Geometry 35 ) Give an informal argument for the formulas for the circumference of a circle; area of a circle; and volume of a cylinder, pyramid, and cone. Use dissection arguments, Cavalieri's principle, and informal limit arguments. [G-GMD1] Alabama Alternate Achievement Standards AAS Standard: M.G.AAS.HS.35- Make a prediction about the volume of a container, the area of a figure, or the perimeter of a figure. Ex: how many cubes will go in one figure vs. another. Limit to cylinder, circle.
Tags: area, circle, circumference, cone, cylinder, formula, pyramid, volume