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 Reflexive Property of Congruence?

Back

The Reflexive Property of Congruence states that any geometric figure is congruent to itself.

Front

What is the Transitive Property of Congruence?

Back

If figure A is congruent to figure B, and figure B is congruent to figure C, then figure A is congruent to figure C.

Front

What is the Transitive Property of Equality?

Back

If a = b and b = c, then a = c.

Front

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

Back

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

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 a transversal?

Back

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

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 congruent.