Parallel Lines and Transversals

Front

What are parallel lines?

Back

Parallel lines are lines in a plane that never meet or intersect, no matter how far they are extended. They are always the same distance apart.

Front

What is a transversal?

Back

A transversal is a line that crosses at least two other lines. When a transversal intersects parallel lines, it creates several angles.

Front

What are corresponding angles?

Back

Corresponding angles are pairs of angles that are in similar positions at each intersection where a transversal crosses two lines. If the lines are parallel, corresponding angles are equal.

Front

What are alternate interior angles?

Back

Alternate interior angles are pairs of angles that lie between two lines and on opposite sides of a transversal. If the lines are parallel, these angles are equal.

Front

What are alternate exterior angles?

Back

Alternate exterior angles are pairs of angles that lie outside two lines and on opposite sides of a transversal. If the lines are parallel, these angles are equal.

Front

What are consecutive interior angles?

Back

Consecutive interior angles are pairs of angles that lie between two lines on the same side of a transversal. If the lines are parallel, these angles are supplementary (add up to 180°).

Front

If m∠1 = 40° and m∠2 is a corresponding angle, what is m∠2?

Back

m∠2 = 40° (because corresponding angles are equal when lines are parallel).

Front

If m∠3 = 90°, what is m∠4 if m∠3 and m∠4 are alternate interior angles?

Back

m∠4 = 90° (because alternate interior angles are equal when lines are parallel).

Front

Solve for x if m∠5 = (3x + 10)° and m∠6 = (2x + 30)° are corresponding angles.

Back

x = 10 (set the equations equal: 3x + 10 = 2x + 30).

Front

What is the relationship between parallel lines and the angles formed by a transversal?

Back

When a transversal intersects parallel lines, specific angle relationships (corresponding, alternate interior, alternate exterior, and consecutive interior) hold true, allowing for angle measures to be determined.