Parallel Lines Cut by a Transversal

Front

What are parallel lines?

Back

Lines in a plane that never meet and are always the same distance apart.

Front

What is a transversal?

Back

A line that intersects two or more lines at different points.

Front

What are vertical angles?

Back

Angles that are opposite each other when two lines intersect; they are equal in measure.

Front

What are alternate interior angles?

Back

Angles that are on opposite sides of the transversal and inside the two lines; they are equal when the lines are parallel.

Front

What are corresponding angles?

Back

Angles that are in the same position at each intersection where a transversal crosses two lines; they are equal when the lines are parallel.

Front

What is the sum of the angles on a straight line?

Back

180 degrees.

Front

What is the relationship between alternate exterior angles when two parallel lines are cut by a transversal?

Back

They are equal.

Front

How do you find the measure of an angle when given its supplementary angle?

Back

Subtract the measure of the supplementary angle from 180 degrees.

Front

What is the relationship between consecutive interior angles when two parallel lines are cut by a transversal?

Back

They are supplementary (add up to 180 degrees).

Front

What is the definition of supplementary angles?

Back

Two angles whose measures add up to 180 degrees.