Math Is Fun
Math Is Fun: Using a Ruler and Drafting Triangle
Students learn how to construct parallel and perpendicular lines. The resource consists of video demonstrations.
Shmoop University
Shmoop: Basic Geometry: Parallel Lines & Transversals
The geometry resource explores parallel lines and transversals. Descriptions, examples, and practice exercises are included.
Sonoma State University
Sonoma State University: Parallel Lines and Similar and Congruent Triangles
This site defines parallel lines, parallel lines cut by a transverse, and congruent triangles. It also contains links for related terms.
Wolfram Research
Wolfram Math World: Parallel Lines
A definition for parallel lines in two-dimensional and three-dimensional Euclidean space. The site also gives reference to skew lines and explains the difference between skew and parallel lines in three-dimensional space.
Quia
Ixl Learning: Parallel and Perpendicular Lines
Brush up on your math skills relating to parallel and perpendicular lines then try some practice problems to test your understanding.
Homeschool Math
Homeschool Math: Parallel and Perpendicular Lines
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.
National Council of Teachers of Mathematics
The Math Forum: Math to Build On: Crossing & Parallel Lines
A definition of parallel lines that draws a comparison to planes and provides drawings for examples.