Handout
CK-12 Foundation

Ck 12: Geometry: Lines and Angles Study Guide

For Students 9th - 10th Standards
This study guide on lines and angles covers key terminology; line notation; parallel, perpendicular, and skew lines; and postulates and theorems about lines. It is available for download with free registration.
Handout
CK-12 Foundation

Ck 12: Geometry: Segments Study Guide

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] This study guide reviews how to measure the distance between two points and the Ruler Postulate. It also introduces congruency/congruent segments and midpoint.
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Aa Similarity

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] Use the AA Similarity Postulate to determine if triangles are similar.
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Sas Triangle Congruence

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] This concept introduces students to the SAS Triangle Postulate and how to prove that two triangles are congruent given only information about two pairs of sides and...
Handout
CK-12 Foundation

Ck 12: Geometry: Angles and Transversals Study Guide

For Students 9th - 10th Standards
This study guide on angles and transversals covers key terms, angle types formed by transversals, postulates and theorems about transversals, and how to prove if lines are parallel or perpendicular. It is available for download with free...
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Sss Triangle Congruence

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] This concept introduces students to the SSS Triangle Congruence Postulate and how to prove that two triangles are congruent given only information about their side...
eBook
CK-12 Foundation

Ck 12: Interactive Geometry: 4.1 Theorems and Proofs

For Students 9th - 10th Standards
Understand theorems and proofs as they relate to geometry.
Handout
CK-12 Foundation

Ck 12: Geometry: Surface Area and Volume Study Guide

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] This study guide looks at the definitions and postulates of surface area and volume for different solids, including composite solids and similar solids.
Handout
CK-12 Foundation

Ck 12: Geometry: Triangle Congruence Study Guide

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] Provides an overview of triangle congruence, including key terms, properties of congruent triangles, triangle postulates and theorems, and special triangles.
Handout
CK-12 Foundation

Ck 12: Geometry: Angles Study Guide

For Students 9th - 10th Standards
This study guide on angles covers key vocabulary, ways to name angles, how to measure them, the Protractor Postulate and the Angle Addition Postulate, types of angles, congruent angles, angle bisectors, and angle pairs. It is available...
Handout
CK-12 Foundation

Ck 12: Geometry: Lines in the Coordinate Plane Study Guide

For Students 9th - 10th Standards
This study guide on lines in a coordinate plane covers key terms, what different line slopes look like, postulates about parallel and perpendicular lines, the slope-intercept equation, how to graph parallel and perpendicular lines, and...
Handout
Wolfram Research

Wolfram Math World: Euclid's Postulates

For Students 9th - 10th
This site from MathWorld.com provides a listing of the postulates of Euclid and a brief discussion on the validity of the fifth postulate.
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Sss Triangle Congruence

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] Prove two triangles are congruent with the Side-Side-Side shortcut.
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Sas Triangle Congruence

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] Prove two triangles are congruent with the Side-Angle-Side shortcut.
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Asa and Aas Triangle Congruence

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] In this lesson students prove two triangles are congruent with the Angle-Side-Angle and Angle-Angle-Side shortcuts. Students examine guided notes, review guided...
eBook
Math Planet

Math Planet: Geometry: Proofs Using Algebra

For Students 9th - 10th Standards
Examples and a video lesson help to explain proofs and logic. [1:57]
Handout
CK-12 Foundation

Ck 12: Geometry: Perimeter and Area Study Guide

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] This study guide looks at the definitions and units for perimeter, area, and circumference, and at the perimeter and area of different shapes, including regular...
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Distance Between Two Points

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] In this lesson students measure the distance between two points. Students examine guided notes, review guided practice, watch instructional videos and attempt...
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Distance Between Two Points

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] In this concept, students will learn how to measure distances using rulers and grids. Students examine guided notes, review guided practice, watch instructional...
Website
Wolfram Research

Wolfram Math World: Euclid: The Elements

For Students 6th - 8th
The classic treatise in geometry written by Euclid is presented in English. It is the textbook used for more than 1,000 years in western Europe.
Activity
Analyze Math

Analyze Math: Congruent Triangle Examples

For Students 9th - 10th Standards
The geometry tutorial investigates congruent triangles. Students learn about the definitions and theorems on congruent triangles. Some topics included are angle-side-angle, side-side-side, and side-angle-side congruence postulates. The...
Handout
Other

The Mathematical Elements of Euclid

For Students 9th - 10th
An extensive discussion of the Elements, which contains all the geometrical knowledge available in the Hellenistic period.
Handout
Jim Loy

Jim Loy's Mathematics Page: Congruence of Triangles

For Students 9th - 10th Standards
Find explanations of the ways to prove triangles are congruent. There is a link for Congruence Of Triangles, Part II to find the proofs of some ways to prove congruence of triangles from other postulates (i.e. Assume SAS prove ASA).
Activity
Texas Instruments

Texas Instruments: Trisecting a Square

For Teachers 9th - 10th Standards
Students will determine several ways to trisect a square. They will use Cabri Jr. to verify the square has been trisected and then prove their trisection using postulates and theorems from geometry. Supplementary worksheets are included...