PARALLEL LINES

Just as the Pythagorean Theorem is an amazing math formula for use with RIGHT Triangles,
there are interesting relationships between angles and parallel lines.

PARALLEL Lines are two (or more lines that do not intersect).
The TRANSVERSAL is a line that crosses the Parallel Lines.

It is important to remember that a LINE has a measure of 180 degrees.
Supplementary Angles add up to 180.
Complementary Angles add up to 90.

The 'Standard' is often the angles are labeled in a 'clockwise'' order and they are labeled with 'Letters' in increasing sequential order. It gets confusing if you label angles with 'Numbers' !
The Letter 'O' is often used for ORIGIN but can be confussed with ZERO.

Given two parallel lines cut by a transversal, there are 8 Angles associations that are formed.
Angles are classified as being External (outside the Parallel Lines) or Internal (Inside the Parallel Lines).

They are also on the Same Side or Opposite Side of the transversal.

Angles may also be Adjacent (share a vertex and a side)
or Vertical (opposite) formed by the intersection of two lines.

Revised: April 29, 2024