[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.

This site offers a brief description of alternate interior angles, followed by an explanatory diagram.

[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...

[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.

Eighth graders are presented with a labeled drawing of two parallel lines intersected by a transversal line. They are asked to discuss congruency of angles when the picture is rotated about a point on the transversal. Aligns with 8.G.A.5.

Explore the triangle inequality theorem with this helpful reference tool. Provides a detailed definition and an interactive activity that enhances further explanation. Includes links to related topics.

This site gives a decription of interior angles along with a visual representation. Be sure to use the links to related terms, everyday examples, challenging problems, more information, and the interactive check point involving interior...

This upper elementary and middle school lesson plan introduces the concept of acute, obtuse and right angles. Also, as the instructional activity proceeds vertical, adjacent, alternate interior and alternate exterior angles are explored....

Students explore the relationships of angles formed when two parallel or non-parallel lines are cut by a transversal. This activity investigates the terms: Transversal, corresponding angles, alternate interior angles, alternate exterior...

Students can use a map of Washington, DC, to travel to/from different tourist locations using vertical angles, corresponding angles, alternate interior angles, alternate exterior angles, same-side interior angles, and linear pairs.

Dr. Math at the Math Forum offers a way of remembering alternate exterior and alternate interior angles by looking at the words and realize what they say and apply it to the picture.

Everything you wanted to know about angles and more, including 1) how to measure angles 2) types of angles 3) angle relationships and 4) angles around a transversal.

This site offers a definition for alternate interior angles with a labeled graph and links to other related words.

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...

This activity from Shodor Education Foundation will help you learn or review your angle vocabulary.

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.

Get the definition for parallel lines and explore angles associated with parallel lines.

Investigate vertically opposite, corresponding, and alternate angles formed by parallel lines and a transversal using this highly interactive Learn Alberta math. Be sure to follow the link to the printable activities, solutions, learning...

Intermath Dictionary's site defines terms relating to angles, gives examples, and offers interactive exercises.

Students are challenged to identify and measure angles created by parallel lines and a transversal as well as complementary and supplementary pairs.

Practice finding angle measures between intersecting 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.

In this task, 8th graders are presented with a drawing of two parallel lines connected through two line segments. They are given the measures of two angles and are asked to find a third. Aligns with 8.G.A.5.

In this activity, students learn and increase their knowledge about the angles formed when parallel lines are cut by a transversal.