Properties of Parallel Lines

Front

What are parallel lines?

Back

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

Front

What is the Corresponding Angles Postulate?

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

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

Front

What is the relationship between Same Side Interior Angles?

Back

If two parallel lines are cut by a transversal, then the same side interior angles are supplementary (add up to 180 degrees).

Front

What are Vertical Angles?

Back

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

Front

How do you find the value of x in angle problems involving parallel lines?

Back

Use the properties of angles formed by a transversal cutting parallel lines to set up equations.

Front

What is the Alternate Exterior Angles Theorem?

Back

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

Front

What is the definition of Transversal?

Back

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

Front

If ∠1 and ∠2 are corresponding angles, what can be said about their measures?

Back

They are equal if the lines are parallel.

Front

What is the sum of the interior angles on the same side of a transversal?

Back

They are supplementary, meaning they add up to 180 degrees.