Parallel & Perpendicular Lines
Big ideas teachers should be aware of and how this topic assists in students understanding of geometry
- Making sure students understand the definitions of parallel (distinct lines lying in the same plane and they never intersect each other) and perpendicular (lines that intersect at right angles) lines before going further into discussion
- Apply real world scenarios for students to relate to the different types of lines (i.e. 4-way intersection, ladder, railroad tracks)
- Addressing the misconception of perpendicular lines and intersecting lines by having students identify properties and relationships between the two. (i.e. Is a perpendicular line always an intersecting line? Is an intersecting line always a perpendicular line?)
- Helping students understand finding angles with the types of lines and asking conceptual questions with the relationships between parallel, perpendicular, and intersecting lines
- Comparing the relationships of the slopes of a set of parallel lines and a set of perpendicular lines. The teacher should be asking students why these slopes are the way they are and have students model and draw the two sets to prove the relationship.
Photo used under Creative Commons from Charlie Day DaytimeStudios