CK-12 Foundation
Ck 12: Geometry: Lines and Angles Study Guide
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.
Khan Academy
Khan Academy: Line and Angle Proofs
Explore different ways of proving some theorems about lines and angles. Some transformations are used. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video, or receive hints.
Khan Academy
Khan Academy: Classifying Shapes by Line and Angle Types
In this exercise, students practice classifying shapes by line and angle types. Students receive immediate feedback and have the opportunity to get hints and try questions repeatedly.
Geometry Help
Geometry Help: Intersecting Lines and Angles
Explains the basic concept of intersecting lines and angles with step-by-step instructions and methods for solving specific problems on your own relating to this topic.
CK-12 Foundation
Ck 12: Interactive Geometry: 1.2 Angles and Lines
Explore lines and angles, and the relationship between the two.
Geometry Help
Geometry Help: Lines and Angles
Explains the basic concept of lines and angles with step-by-step instructions and methods for solving specific problems on your own relating to this topic.
CK-12 Foundation
Ck 12: Interactive Geometry: 4.3 Applications of Line and Angle Theorems
Learn the four categories of theorems that have to do with lines and angles.
CK-12 Foundation
Ck 12: Interactive Geometry: 4.2 Theorems About Lines and Angles
Consider two parallel lines that are intersected by a transversal, and when it crosses the two others, many different angle pairs are formed. See the special properties of the angle pairs in this interactive.
Mr. Martini's Classroom
Mr. Martini's Classroom: Basic Geometry: Points, Lines, and Angles
Students can review basic geometric terms using these self-check, multiple choice questions. Three levels of questions are provided.
Annenberg Foundation
Annenberg Learner: Geometry: Circles: Inscribed Angles
Study inscribed angles in semicircles and quarter-circles. What conjectures can you make about the measure of an inscribed angle in semi- or quarter-circles?
Analyze Math
Analyze Math: Parallel Lines and Angles Problems
Try these three problems about finding the measures of different angles that arise from diagrams involving parallel lines and transversals. Detailed solutions are written out for these three problems of moderate difficulty.
CK-12 Foundation
Ck 12: Geometry: Alternate Interior Angles
[Free Registration/Login may be required to access all resource tools.] Use alternate interior angles to determine angle congruency and the presence of parallel lines.
CK-12 Foundation
Ck 12: Geometry: Alternate Exterior Angles
[Free Registration/Login may be required to access all resource tools.] Use alternate exterior angles to determine congruency and the presence of parallel lines.
CK-12 Foundation
Ck 12: Geometry: Alternate Exterior Angles Intermediate
[Free Registration/Login may be required to access all resource tools.] This concept introduces students to alternate exterior angles and how to use them to determine whether or not lines are parallel.
Other
800score: Intersecting Angles
Read a description of intersecting lines and all about the different kinds of angles they form. Includes examples.
Homeschool Math
Homeschool Math: Lines, Rays, and Angles
This fourth-grade geometry instructional activity teaches the definitions for a line, ray, angle, acute angle, right angle, and obtuse angle. We also study how the size of the angle is ONLY determined by how much it has "opened" as...
Oswego City School District
Regents Exam Prep Center: Geometry Vocabulary Resources
A list of geometry definitions and a matching activity.
Oswego City School District
Regents Exam Prep Center: Parallel Lines
Material to supplement classroom instruction on parallel lines: a lesson on angles with parallel lines, a practice quiz, and a link to an investigation on angles with parallel and non-parallel lines.
Cuemath
Cuemath: Angles
A comprehensive guide for learning all about angles with definitions, examples, and practice questions.
CK-12 Foundation
Ck 12: Geometry: Alternate Interior Angles Intermediate
[Free Registration/Login may be required to access all resource tools.] This concept introduces students to alternate interior angles and how to use them to determine whether or not lines are parallel.
CK-12 Foundation
Ck 12: Perpendicular Lines
[Free Registration/Login Required] Students explore the concept of perpendicular lines by navigating through the interactive learning module and then answering questions that go along with the module. Students can also learn more about...
Mr. Martini's Classroom
Mr. Martini's Classroom: Geometry Special Angle Pairs and Parallel Transversals
Students are challenged to identify and measure angles created by parallel lines and a transversal as well as complementary and supplementary pairs.
CK-12 Foundation
Ck 12: Geometry: Same Side Interior Angles
[Free Registration/Login may be required to access all resource tools.] This concept introduces students to same side interior angles and how to use them to determine whether or not lines are parallel.
CK-12 Foundation
Ck 12: Geometry: Parallel and Perpendicular Lines
[Free Registration/Login may be required to access all resource tools.] Identifying types of lines as parallel lines, perpendicular lines or intersecting lines.