National Council of Teachers of Mathematics
The Math Forum: Ask Dr. Math: Standard Form of a Line
Dr. Math gives an inspiring and clear discussion about equations of lines and lines as functions. The Dr. discusses the benefits of the standard form of a line and prompts the student with an equation which can not be written in the...
Texas Instruments
Texas Instruments: Investigating the Slopes of Parallel and Perpendicular Lines
In this activity, students investigate how equations of parallel and perpendicular lines relate to each other. They use the drawing and measurement tools of Cabri Jr. to explore the slopes of lines. [Requires Adobe Reader.]
CK-12 Foundation
Ck 12: Parallel Lines
[Free Registration/Login Required] Students explore the concept of parallel lines by navigating through the interactive learning module and then answering questions that go along with the module. Students can also learn more about the...
University of Regina (Canada)
University of Regina: Math Central: Introduction to Slope for Middle Years Mathematics
This collection of five middle school math lessons covers the topic of plane geometry, specifically the concept of slope. The first lesson introduces students to plotting points on a Cartesian grid using a Geoboard. Lesson two moves them...
Texas Instruments
Texas Instruments: Mc Dougal Littell Geometry: Investigate Slopes
Students can use the TI-84 Plus family with Cabri Jr. to investigate properties of parallel lines.
Oswego City School District
Regents Exam Prep Center: Slopes and Equations of Lines
Three resources for teaching slopes and equations of lines: a lesson with a formula for finding slope, different equations for lines, and several examples; a fourteen-question quiz covering slope, perpendicular and parallel lines, and...
CK-12 Foundation
Ck 12: Algebra: Equations of Perpendicular Lines
[Free Registration/Login may be required to access all resource tools.] This lesson covers determining if two lines are parallel, perpendicular, or neither and finding the equation of perpendicular lines to a given line.
ClassFlow
Class Flow: Slope of Parallel Lines
[Free Registration/Login Required] This flipchart investigates the idea that linear equations that have the same slope will create parallel lines. We did some samples in class and then students are to predict what happens when equations...
Other
Git: What Is the Slope Intercept Form of a Line?
Not only does this site show what the slope-intercept form is, but it helps you find the slope and the intercept of a line. There is also additional information on parallel lines, parametric form, and the distance between two points.
ClassFlow
Class Flow: Slope of Parallel Lines
[Free Registration/Login Required] Given slope and y-intercept (or a point) can you create the equation for a line parallel to that line (and then graph it)?
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: Algebra: Comparing Equations of Parallel and Perpendicular Lines
[Free Registration/Login may be required to access all resource tools.] Use their slopes to determine if two lines are parallel or perpendicular.
National Council of Teachers of Mathematics
The Math Forum: Lines and Slope: Chameleon Graphing
Join Joan the chameleon in an exploration of lines and slope. You'll be drawing lines, calculating slope, using equations and more!
CK-12 Foundation
Ck 12: Algebra: Comparing Equations of Parallel and Perpendicular Lines
Use their slopes to determine if two lines are parallel or perpendicular.
Texas Instruments
Texas Instruments: Geometry: Parallel and Perpendicular Slopes
This activity will help students understand the relationship between the slopes of parallel and perpendicular lines.
Texas Instruments
Texas Instruments: Lines in the Plane
In this activity, students create a slope triangle and understand the concepts of slope and the equation of lines. They realize that slope is constant at all points along a fixed line. They also explore the slopes of parallel and...
Northeast Parallel Architectures Center, Syracuse University
Npac Reu Program: Parallel and Perpendicular Lines
Northeast Parallel Architecture Center, Syracuse University provides a brief definition of the slopes of parallel and perpendicular lines
Varsity Tutors
Varsity Tutors: Hotmath: Slope, Parallel & Perpendicular Lines & Transversals
Twenty-five problems cover the topics of slope, parallel lines, perpendicular lines, and transversals in different settings. They are given with each step to the solution cleverly revealed one at a time. You can work each step of the...
Texas Instruments
Texas Instruments: Parallel and Perpendicular Lines on Ti Smartview
This is an introductory lesson on graphing parallel and perpendicular lines. The students will have a good visual on how these lines relate to each other. This also illustrates how to determine equations in slope-intercept form of a line...
Sophia Learning
Sophia: Writing a Linear Equation From a Parallel Line and Point: Lesson 1
This lesson presents how to write an equation of a line that passes through a given point and is parallel to a given line. It is 1 of 5 in the series titled "Writing a Linear Equation from a Parallel Line and Point."
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...
Northeast Parallel Architectures Center, Syracuse University
Npac Reu Program: Slope
This Northeast Parallel Architecture Program, Syracuse University site explains and illustrates by using the changes in the values of x and y you can determine the slope of a line.
CK-12 Foundation
Ck 12: Algebra: Families of Lines
[Free Registration/Login may be required to access all resource tools.] Find the equation of a line that is parallel or perpendicular to a given line.
Northeast Parallel Architectures Center, Syracuse University
Npac Reu Program: Tangent Lines
The Northeast Parallel Architectures Center at Syracuse University offers a fairly detailed site explaining the slope of a tangent line to a curve.