Parallel and Perpendicular Lines

Parallel and Perpendicular Lines

Mathematics problems often deal with parallel and perpendicular lines.
Since these are such popular lines, it is important that we remember some information about their slopes.

Parallel and Perpendicular Lines 1

Parallel Lines: (same slope!)

Parallel and Perpendicular Lines 2

Parallel lines are marked with “feathers” to show that they are parallel.
These “feathers” look like “greater than” symbols.

Parallel lines have the same slope.
The symbol to indicate parallel lines is two vertical bars.
It looks something like the number 11.

 

Perpendicular Lines: (negative reciprocal slopes!)

Parallel and Perpendicular Lines 3

Perpendicular lines have negative reciprocal slopes.
The symbol to indicate perpendicular is an up-side-down capital T.

Parallel and Perpendicular Lines 4