Texas Instruments
Texas Instruments: Perpendicular Slope
Students will "discover" that perpendicular lines have negative reciprocal slopes. [Requires Adobe Reader.]
Varsity Tutors
Varsity Tutors: Hotmath: Graphing Calculator: Parallel, Perpendicular, Slope, Transversal
Practice using your graphing calculator for drawing parallel lines, perpendicular lines, slope, and transversals. If you get stumped or if you would like to check your work, then select the View Solution button, which is located directly...
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...
Varsity Tutors
Varsity Tutors: Hotmath: Algebra Review: Perpendicular and Parallel Lines
Find a quick, concise explanation of what perpendicular lines are. An example is given and clearly explained. Also, parallel lines are explained.
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!
Illustrative Mathematics
Illustrative Mathematics: G Gpe When Are Two Lines Perpendicular?
The goal of this task is to examine when two lines in the plane are perpendicular in terms of their slopes. Aligns with HSG-GPE.B.5.
Varsity Tutors
Varsity Tutors: Hotmath: Practice Problems: Perpendicular and Parallel Lines
Twenty-two problems present a variety of practice working with perpendicular and parallel lines. 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...
Texas A&M University
Wtamu Virtual Math Lab: College Algebra: Parallel and Perpendicular Lines
Given a line, learn how to find the equations for lines that are perpendicular and parallel to it. This tutorial offers several example graphs and problems as well as practice problems for you to work through when you're ready.
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...
PBS
Pbs Learning Media: Math + Arts: Perspective Drawing
In this lesson plan, students use line segments, angles, and parallel and perpendicular lines in order to create a one point perspective drawing.
Wolfram Research
Wolfram Math World: Perpendicular Lines
This site explains what perpendicular means geometricly in mathematics, gives reference to orthoginality, and explains notation for perpendicular segments or lines.
CK-12 Foundation
Ck 12: Elem Math: Determining Whether Lines Are Perpendicular
[Free Registration/Login may be required to access all resource tools.] Students watch two videos and attempt practice problems on how to determine if two lines are perpendicular.
CK-12 Foundation
Ck 12: Geometry: Lines and Angles Study Guide
This study guide on lines and angles covers key terminology; line notation; parallel, perpendicular, and skew lines; and postulates and theorems about lines. It is available for download with free registration.
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.
University of North Carolina
University of North Carolina Wilmington: Lines in a Plane
This site from the University of North Caroline at Wilmington provides great information on the lines in a plane. The information that is given is in-depth and complete, touching on the slope of a line, equations of lines, and linear...
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...
University of Georgia
University of Georgia: Inter Math: Perpendicular Lines
This site from InterMath opens with a very simple definition of perpendicular lines and has links to challenging problems, more information, related terms and everyday examples of perpendicular lines.
Texas Instruments
Texas Instruments: Getting Started With Ti Navigator: Parallel and Perpendicular
This lesson introduces students to Activity Center and is intended to help students interpret whether lines are parallel or perpendicular. [Requires Adobe Reader.]
Texas Instruments
Texas Instruments: Parallel and Perpendicular Slopes
This activity is for use as a formative assessment tool after the introduction and overview of parallel and perpendicular slopes.
Purple Math
Purplemath: Slope of a Straight Line
This lesson on slope explains the slope concepts, demonstrates how to use the slope formula, shows how to find slope in horizontal and vertical lines, and how to use slope to find whether the lines through the pairs of points are...
Illustrative Mathematics
Illustrative Mathematics: G C, G Co Tangent Lines and the Radius of a Circle
In this task, students are shown a circle with center O and point P on the circle. L is a line that is a tangent to the circle at P. They must show that line OP is perpendicular to line L. Aligns with G-C.A.2, G-CO.A, and G-CO.C.9.
Illustrative Mathematics
Illustrative Mathematics: G Srt Shortest Line Segment From a Point P to a Line L
In this task, students develop an understanding that the shortest path from a point to a line always meets the line at a right angle. Aligns with G-SRT.C.8.
Math Open Reference
Math Open Reference: Points and Lines
A complete reference guide to points, lines, and planes. It provides definitions and interactive activities that enhance further explanation.
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.