Front

What condition proves that two lines are parallel?

Back

If two lines are cut by a transversal and the alternate interior angles are congruent, then the lines are parallel.

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

Back

If two lines are parallel, then corresponding angles are congruent.

Front

What must be true about consecutive interior angles for two lines to be parallel?

Back

Consecutive interior angles must be supplementary (add up to 180 degrees) for the lines to be parallel.

Front

What does it mean if two angles are supplementary?

Back

Two angles are supplementary if the sum of their measures is 180 degrees.

Front

Can two lines be proven parallel if alternate exterior angles are congruent?

Back

Yes, if alternate exterior angles are congruent, then the lines are parallel.

Front

What is a transversal in geometry?

Back

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

Front

What is the significance of angle pairs in proving lines parallel?

Back

Angle pairs such as alternate interior angles, corresponding angles, and consecutive interior angles help determine if lines are parallel.

Front

What is the converse of the alternate interior angle theorem?

Back

If two lines are cut by a transversal and the alternate interior angles are congruent, then the lines are parallel.

Front

What is the relationship between vertical angles?

Back

Vertical angles are always congruent, which can be useful in proving lines parallel.