City University of New York
Lehman College: An Introduction to Lines
Use this site for two short lesson plans regarding Euclidean and Spherical lines. Intersecting and parallel lines are discussed. The lesson contains activities for two days of class.
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: 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 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: Lines in the Coordinate Plane Study Guide
This study guide on lines in a coordinate plane covers key terms, what different line slopes look like, postulates about parallel and perpendicular lines, the slope-intercept equation, how to graph parallel and perpendicular lines, and...
Khan Academy
Khan Academy: Parallel and Perpendicular Lines From Graph
Given points that two lines go through or the graph of each line, classify the lines as parallel, perpendicular, or neither. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or...
Khan Academy
Khan Academy: Write Equations of Parallel and Perpendicular Lines
Write the equation for a line that is a parallel or perpendicular to a line given in slope-intercept form and that goes through a specific point. Students receive immediate feedback and have the opportunity to try questions repeatedly,...
Khan Academy
Khan Academy: Parallel and Perpendicular Lines From Equation
Use your knowledge about the slopes of parallel and perpendicular lines to solve some problems. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
CK-12 Foundation
Ck 12: Geometry: Corresponding Angles
[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...
CK-12 Foundation
Ck 12: Geometry: Angles and Transversals Study Guide
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...
Math Planet
Math Planet: Pre Algebra: Geometry Fundamental Statements
Provides examples and a video lesson that introduce fundamental statements of geometry.
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: Corresponding Angles
[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...
CK-12 Foundation
Ck 12: Geometry: Corresponding Angles
[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...
Varsity Tutors
Varsity Tutors: Hotmath: Practice Problems: Geometry in the Plane
Twenty-four problems presented on a variety of Plane Geometry topics. They are given with each step to the solution cleverly revealed one at a time. You can work each step of the problem then click the "View Solution" button to check...
Texas Instruments
Texas Instruments: Parallel or Perpendicular What's Your Inclination?
This activity has students discover the relationship between parallel and perpendicular lines and their slopes. After constructing these objects using CABRI Geometry II for the TI-89, slopes are measured. [Requires Adobe Reader.]
Texas Instruments
Texas Instruments: Cabri Geometry Tour
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.
McGraw Hill
Glencoe : Online Study Tools: Quiz on Parallel & Perpendicular Lines
Learners exhibit comprehension of advanced mathematics skills in Geometry. The questions check understanding on parallel and perpendicular lines.
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.
Texas Education Agency
Texas Gateway: Writing Geometric Relationships
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...
Texas Education Agency
Texas Gateway: Coordinate Geometry: Special Segments
The student will derive and use the slope and midpoint formulas to verify geometric relationship that include parallelism and perpendicularity of lines. Then, the student will determine an equation of a line parallel or perpendicular to...
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: 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: 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.