In this unit, students learn to find areas of polygons by decomposing, rearranging, and composing shapes. They learn to understand and use the terms “base” and “height,” and find areas of parallelograms and triangles. Students approximate areas of non-polygonal regions by polygonal regions. They represent polyhedra with nets and find their surface areas.

This task examines the ways in which the plane can be covered by regular polygons in a very strict arrangement called a regular tessellation. These tessellations are studied here using algebra, which enters the picture via the formula for the measure of the interior angles of a regular polygon (which should therefore be introduced or reviewed before beginning the task). The goal of the task is to use algebra in order to understand which tessellations of the plane with regular polygons are possible.

This lesson unit is intended to help you assess how well students are able to use geometric properties to solve problems. In particular, it will support you in identifying and helping students who have the following difficulties: Solving problems relating to using the measures of the interior angles of polygons; and solving problems relating to using the measures of the exterior angles of polygons.

This book is a "flexed" version of CK-12's Basic Geometry that aligns with College Access Geometry and contains embedded literacy supports. It covers the essentials of geometry for the high school student.

CK-12 Foundation's Geometry FlexBook is a clear presentation of the essentials of geometry for the high school student. Topics include: Proof, Congruent Triangles, Quadrilaterals, Similarity, Perimeter & Area, Volume, and Transformations.

This lesson focuses on calculating the areas of rectangles. It is designed to enable adult students to successfully master basic geometry knowledge in order to achieve their High School Equivalency (HSE). Areas to be covered include types of polygons, quadrilaterals, rectangles; calculating areas of rectangle and calculating costs. Students will apply this knowledge to practical areas of their lives such as calculating the costs of purchasing carpets or painting of walls

This lesson focuses on calculating the areas of rectangles. It is designed to enable adult students to successfully master basic geometry knowledge in order to achieve their High School Equivalency Diploma (HSED). Areas to be covered include types of polygons, quadrilaterals, rectangles; calculating areas of rectangles and calculating costs. Students can apply this knowledge to practical areas of their lives such as calculating the cost of purchasing carpet or painting walls.

In this video segment from Cyberchase, the CyberSquad measures Judge Trudy's land claim by using tarps, fence posts and a grid made with rope.

This lesson focuses on calculating the areas of rectangles. It is designed to enable adult students to successfully master basic geometry knowledge in order to achieve their High School Equivalency (HSE). Areas to be covered include types of polygons, quadrilaterals, rectangles; calculating areas of rectangle and calculating costs. Students will apply this knowledge to practical areas of their lives such as calculating the costs of purchasing carpets or painting of walls

The CyberSquad proves that the area of Hacker's land is equal to the area of Judge Trudy's land in this video segment from Cyberchase.

Students explore how the formulas for the areas of parallelograms, triangles, and trapezoids are developed. 

The purpose of this task is to have students work on a sequence of area problems that shows the advantage of increasingly abstract strategies in preparation for developing general area formulas for parallelograms and triangles.

A structured geometry program teacher edition of daily lesson plans and teacher supports to accompany the College Access Reader: Geometry student edition.

CK-12 Foundation's Geometry FlexBook is a clear presentation of the essentials of geometry for the high school student. Topics include: Proof, Congruent Triangles, Quadrilaterals, Similarity, Perimeter & Area, Volume, and Transformations.

CK-12's Geometry - Second Edition is a clear presentation of the essentials of geometry for the high school student. Topics include: Proofs, Triangles, Quadrilaterals, Similarity, Perimeter & Area, Volume, and Transformations.

CK-12 Geometry Teacher's Edition covers tips, common errors, enrichment, differentiated instruction and problem solving for teaching CK-12 Geometry Student Edition. The solution and assessment guides are available upon request.

In Module 3, students learn about dilation and similarity and apply that knowledge to a proof of the Pythagorean Theorem based on the Angle-Angle criterion for similar triangles.  The module begins with the definition of dilation, properties of dilations, and compositions of dilations.  One overarching goal of this module is to replace the common idea of “same shape, different sizes” with a definition of similarity that can be applied to geometric shapes that are not polygons, such as ellipses and circles.

Find the rest of the EngageNY Mathematics resources at https://archive.org/details/engageny-mathematics.

The goal of this task is to use geometry study the structure of beehives. Beehives have a tremendous simplicity as they are constructed entirely of small, equally sized walls. In order to as useful as possible for the hive, the goal should be to create the largest possible volume using the least amount of materials. In other words, the ratio of the volume of each cell to its surface area needs to be maximized. This then reduces to maximizing the ratio of the surface area of the cell shape to its perimeter.

This task asks students to identify which of the six polygons have the same area. Students may complete the task using a variety of techniques including decomposing shapes, using transformations (rotations, reflections, translations) to move one or more parts of the figure to another part to more easily calculate the area, enclosing the polygon inside a larger rectangle and then subtract the areas of the "extra" pieces, etc.