Parallel lines (theorems and converses)

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 lie between two parallel lines on opposite sides of a transversal.

Front

What is the Alternate Interior Angles Theorem?

Back

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

Front

What are vertical angles?

Back

Angles that are opposite each other when two lines intersect.

Front

What is the Vertical Angles Theorem?

Back

Vertical angles are always equal.

Front

What are supplementary angles?

Back

Two angles that add up to 180 degrees.

Front

If ∠4 ≅ ∠6, what can be concluded about lines l and m?

Back

Lines l and m are parallel.

Front

What is the definition of corresponding angles?

Back

Angles that are in the same position on two parallel lines in relation to a transversal.

Front

What is the Consecutive Interior Angles Theorem?

Back

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