Parallel lines and transversals

Front

What are parallel lines?

Back

Parallel lines are lines in a plane that never meet; they are always the same distance apart.

Front

What is a transversal?

Back

A transversal is a line that crosses at least two other lines in the same plane.

Front

What are corresponding angles?

Back

Corresponding angles are pairs of angles that are in similar positions at each intersection where a transversal crosses two lines.

Front

What are alternate interior angles?

Back

Alternate interior angles are pairs of angles that lie between two lines and on opposite sides of a transversal.

Front

What are alternate exterior angles?

Back

Alternate exterior angles are pairs of angles that lie outside two lines and on opposite sides of a transversal.

Front

What are consecutive interior angles?

Back

Consecutive interior angles are pairs of angles that lie between two lines and on the same side of a transversal.

Front

What is the relationship between corresponding angles when two lines are parallel?

Back

When two lines are parallel, corresponding angles are equal.

Front

What is the relationship between alternate interior angles when two lines are parallel?

Back

When two lines are parallel, alternate interior angles are equal.

Front

What is the relationship between consecutive interior angles when two lines are parallel?

Back

When two lines are parallel, consecutive interior angles are supplementary (add up to 180 degrees).

Front

If two lines are cut by a transversal and the corresponding angles are equal, what can be concluded?

Back

If the corresponding angles are equal, then the two lines are parallel.