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 and have the same slope.

Front

What is a transversal?

Back

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

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

Back

If two parallel lines are cut by a transversal, then each pair of corresponding angles is equal.

Front

What are alternate interior angles?

Back

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

Front

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

Back

If two parallel lines are cut by a transversal, then each pair of alternate interior angles is equal.

Front

What are consecutive interior angles?

Back

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

Front

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

Back

If two parallel lines are cut by a transversal, then each pair of consecutive interior angles is supplementary (adds up to 180 degrees).

Front

If angle 1 = 27° and lines are parallel, what is the measure of angle 2?

Back

Angle 2 = 27° (corresponding angle).

Front

If angle 3 = 60°, what is the measure of angle 4 if lines are parallel?

Back

Angle 4 = 120° (consecutive interior angles).