Proving Parallel Lines

Front

What is the definition of parallel lines?

Back

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

Front

What is a transversal in geometry?

Back

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

Front

What does it mean for angles to be congruent?

Back

Congruent angles are angles that have the same measure.

Front

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

Back

When two parallel lines are cut by a transversal, the alternate interior angles are congruent.

Front

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

Back

When two parallel lines are cut by a transversal, the corresponding angles are congruent.

Front

What does it mean for angles to be supplementary?

Back

Supplementary angles are two angles whose measures add up to 180 degrees.

Front

How can you prove that two lines are parallel using angle relationships?

Back

If a pair of alternate interior angles are congruent, or if a pair of corresponding angles are congruent, then the lines are parallel.

Front

What is the significance of the angle pairs formed by a transversal?

Back

The angle pairs formed by a transversal can help determine whether the lines it intersects are parallel.

Front

What is the value of x if two parallel lines are cut by a transversal and the corresponding angle measures are given?

Back

To find x, set up an equation based on the relationships of the angles (e.g., corresponding angles, alternate interior angles) and solve.

Front

What is the relationship between same-side interior angles when two lines are parallel?

Back

When two parallel lines are cut by a transversal, the same-side interior angles are supplementary.