Parallel Lines and Transversals

Front

What are parallel lines?

Back

Parallel lines are lines in a plane that never meet. They are always the same distance apart and have the same slope.

Front

What is a transversal?

Back

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

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.

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.

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.

Front

What are vertical angles?

Back

Vertical angles are the angles opposite each other when two lines cross. They are always equal.

Front

If two lines are cut by a transversal and the corresponding angles are equal, what can be concluded?

Back

If the corresponding angles are equal, then the two lines are parallel.

Front

If two lines are cut by a transversal and the alternate interior angles are equal, what can be concluded?

Back

If the alternate interior angles are equal, then the two lines are parallel.

Front

What is the Linear Pair Postulate?

Back

If two angles form a linear pair, they are supplementary, meaning their measures add up to 180 degrees.

Front

How do you find the measure of an angle when given its relationship to another angle?

Back

Use the properties of angles (like corresponding, alternate interior, etc.) to set up an equation and solve for the unknown angle.