Parallel Lines and Transversals

Front

What are parallel lines?

Back

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

Front

What is a transversal?

Back

A transversal is a line that crosses at least two other lines.

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 are on opposite sides of the transversal and inside the two lines.

Front

What are vertical angles?

Back

Vertical angles are the angles opposite each other when two lines cross. They are always congruent.

Front

What does it mean for angles to be congruent?

Back

Congruent angles are angles that have the same measure.

Front

How can you identify corresponding angles when given a transversal?

Back

Look for angles that are in the same relative position at each intersection created by the transversal.

Front

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

Back

When the lines are parallel, alternate interior angles are congruent.

Front

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

Back

When the lines are parallel, corresponding angles are congruent.

Front

What is the relationship between vertical angles?

Back

Vertical angles are always congruent, regardless of whether the lines are parallel.