Angles, parallel lines, and transversals are explained through examples and a video lesson. [1:01]

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.

Explains the terms and symbols used to discuss line angles, what an angle is, and the types of angles. Includes short video lesson demonstrating how to use a protractor to measure an angle. [0:57]

A list of geometry definitions and a matching activity.

[Free Registration/Login may be required to access all resource tools.] This concept teaches students how to find angles on and inside a circle created by chords and tangent lines.

[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.

[Free Registration/Login may be required to access all resource tools.] This concept teaches students about corresponding angles, and how to use them to determine whether or not lines are parallel. Students examine guided notes, review...

[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.

[Free Registration/Login may be required to access all resource tools.] Identifying adjacent angles and vertical angles formed by intersecting lines

[Free Registration/Login may be required to access all resource tools.] Identifying types of lines as parallel lines, perpendicular lines or intersecting lines.

[Free Registration/Login may be required to access all resource tools.] This concept teaches students about perpendicular lines.

[Free Registration/Login may be required to access all resource tools.] This concept teaches students how to calculate angles formed outside a circle by tangent and secant lines.

[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.

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.

[Free Registration/Login may be required to access all resource tools.] Apply the definitions of midpoint, segment bisector, and angle bisector.

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.

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.

[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.

[Free Registration/Login may be required to access all resource tools.] In this lesson students identify corresponding angles formed when a line intersects two other lines. Students examine guided notes, review guided practice, watch...

[Free Registration/Login may be required to access all resource tools.] In this lesson students identify corresponding angles formed when a line intersects two other lines. Students examine guided notes, review guided practice, watch...

[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.

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.

[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...

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.