CK-12 Foundation
Ck 12: Geometry: Linear Pairs
[Free Registration/Login may be required to access all resource tools.] Identifying adjacent angles and vertical angles formed by intersecting lines
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.
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.
Math Planet
Math Planet: Geometry: Angles, Parallel Lines and Transversals
Angles, parallel lines, and transversals are explained through examples and a video lesson. [1:01]
CK-12 Foundation
Ck 12: Interactive Geometry: 1.2 Angles and Lines
Explore lines and angles, and the relationship between the two.
Math Planet
Math Planet: An Introduction to Geometry
Provides an introduction to geometry with definitions of points, lines, planes and angles through the use of examples and a brief video lesson. [1:28]
Math Slice
Math Slice: Geometry Slice Special Test
A succinct test for assessing geometry concepts. Assessment is scored online giving immediate feedback. An excellent assessment tool.
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: 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.
Math Planet
Math Planet: Pre Algebra: Angles and Parallel Lines
Explains angles and parallel lines through examples and a video lesson.
Homeschool Math
Homeschool Math: Lines, Rays, and Angles
This fourth-grade geometry lesson 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 compared to the whole...
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.
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?
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.
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.
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: Perpendicular Lines
[Free Registration/Login may be required to access all resource tools.] This concept teaches students about perpendicular lines.
Khan Academy
Khan Academy: Angle Relationships With Parallel Lines
Find missing angles given two parallel lines and a transversal. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video, or receive hints.
CK-12 Foundation
Ck 12: Geometry: Same Side Interior Angles
[Free Registration/Login may be required to access all resource tools.] Use same side interior angles to determine supplementary angles and the presence of parallel lines.
CK-12 Foundation
Ck 12: Alternate Interior Angles
[Free Registration/Login Required] Students explore the concept of alternate interior angles by navigating through the interactive learning module and then answering questions that go along with the module. Students can also learn more...
Khan Academy
Khan Academy: Equation Practice With Angles
In this practice activity, students calculate angles created when two parallel lines are intersected by a transversal. Students receive immediate feedback and have the opportunity to watch a video, get hints, or try questions repeatedly.
Khan Academy
Khan Academy: Finding Angle Measures Between Intersecting Lines
Practice finding angle measures between intersecting lines.
Math Planet
Math Planet: Pre Algebra: Geometry Fundamental Statements
Provides examples and a video lesson that introduce fundamental statements of geometry.