In this instructional activity, students will learn important definitions about angles relationships an use those facts to solve equations.

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.

Given algebraic expressions that represent a pair of two vertical angles, form and solve an equation. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.

In this task, 8th graders are presented with a drawing of two parallel lines with a triangle touching them at all three of its vertices. They are asked to prove that the sum of the triangles' angles equals 180 degrees. Aligns with 8.G.A.5.

You can pick up some valuable pointers on angles and lines here. When you finish working your way through the pages you can take an on-line "Test Bite," and check your understanding.

Learn about corresponding angles with this resource which offers detailed explanations and examples. Subjects covered include parallel and non-parallel cases. Links to related topics.

[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...

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?

In this activity, students use the Cabri software to mark points, draw lines, construct parallel and perpendicular lines, angles, bisectors, and triangles. They learn how to use the tool to measure angles.

Students can review basic geometric terms using these self-check, multiple choice questions. Three levels of questions are provided.

[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 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...

Explain that corresponding angles are the result of parallel lines being crossed by another line.

A guide to support parents as they work with their students in angle measure and plane figures.

The lesson investigates special pairs of angles. Topics explored include complementary, supplementary, and vertical angles. Students learn about the concept and view diagrams and exercises with solutions.

This lesson explains what are parallel and perpendicular lines and includes varied exercises and a video that shows how to draw a perpendicular line and a rectangle using a protractor or a triangular ruler.

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.

Given information in a geometric context, students will be able to use informal arguments to establish facts about the angle sum and exterior angle of triangles, the angles created when parallel lines are cut by a transversal, and the...

The students will explore angles, rays, line segments, perpendicular lines, parallel lines, and two-dimensional figures through the use of the book Shape Up! Fun With Triangles and Other Polygons by David A. Adler. They will also...

[Free Registration/Login may be required to access all resource tools.] This study guide looks at proportionality theorems for triangles and parallel lines intersected by transversals.

In this lesson, learners use line segments, angles, and parallel and perpendicular lines in order to create a one point perspective drawing.

Learn all about the basic geometric constructions in this test prep lesson. You will explore line segments and points, and understand key terms like the terms parallel and perpendicular. Construction activities and interactive online...