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.
Texas A&M University
Wtamu Virtual Math Lab: Intermediate Algebra: The Slope of a Line
This tutorial will show you how to find a the slope of graph, write a linear equation in slope-intercept form. You'll also learn how to determine whether two lines are parallel or perpendicular to each other. For advanced math students.