Parallel Lines Cut by a Transversal (With Algebra)

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

How do you find the measure of an angle formed by a transversal?

Back

To find the measure of an angle formed by a transversal, use the relationships between the angles (corresponding, alternate interior, etc.) based on whether the lines are parallel.

Front

If one angle is 130°, what is the measure of its corresponding angle?

Back

If one angle is 130°, its corresponding angle is also 130° because corresponding angles are equal when lines are parallel.

Front

Solve for x: If 2x + 30 = 90, what is x?

Back

x = 30. (Subtract 30 from both sides: 2x = 60, then divide by 2.)

Front

If two angles are supplementary and one angle measures 95°, what is the measure of the other angle?

Back

The other angle measures 85° because supplementary angles add up to 180° (180° - 95° = 85°).