Parallel Lines

Parallel Lines

Concept

Figure out if lines are parallel, perpendicular, or intersecting.

Rules

1. If the lines run alongside each other, but never meet, they are parallel. The symbol for parallel is ∥
2. If the lines meet at a right angle (90°), they are perpendicular. The symbol for perpendicular is ⟂
3. If the lines meet (but not at a right angle) and share one point, they are intersecting.

Example

Which figure shows \fn_phv {\color{Teal} \vec{MN } \parallel \vec{PQ}}

Solution


The lines do not meet. Therefore, they are parallel.

Practice Parallel Lines

Practice Problem 1

Select the correct statement.
Parallel Lines - Practice Problem 1

Practice Problem 2

Select the statement that best describes the relationship between the lines.
Parallel Lines - Practice Problem 2

Practice Problem 3

Which figure shows \fn_phv {\color{Teal} \vec{MN } \parallel \vec{CD}}
Parallel Lines - Practice Problem 3

Practice Problem 4

Match each figure to the correct statement.
Parallel Lines - Practice Problem 4

Parallel lines are two or more lines that never intersect.

Perpendicular lines are two lines that intersect at a right angle.

Intersecting lines are two lines that share exactly one point.

Pre-requisite Skill
Lines, Segments and Rays