Proving Lines Parallel

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 the Converse of the Alternate Interior Angles 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 Transitive Property of Congruence?

Back

If two figures are congruent to a third figure, then they are congruent to each other.

Front

What is the Reflexive Property of Congruence?

Back

Any geometric figure is congruent to itself.

Front

What is the Converse of the Corresponding Angles Postulate?

Back

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

Front

What is the definition of a transversal?

Back

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

Front

What is the definition of same-side interior angles?

Back

Same-side interior angles are pairs of angles on the same side of the transversal and inside the two lines.

Front

What is the Converse of the Same-Side Interior Angles Theorem?

Back

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

Front

What does it mean for angles to be supplementary?

Back

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

Front

What is the definition of corresponding angles?

Back

Corresponding angles are pairs of angles that are in the same position on two different lines cut by a transversal.