Transversal in Geometry: Definition & Angles

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: What is a Hexagon? - Definition, Area & Angles

You're on a roll. Keep up the good work!

Take Quiz Watch Next Lesson
Your next lesson will play in 10 seconds
  • 0:01 What Is a Transversal?
  • 0:23 Angles
  • 2:12 Lesson Summary
Save Save Save

Want to watch this again later?

Log in or sign up to add this lesson to a Custom Course.

Log in or Sign up

Speed Speed

Recommended Lessons and Courses for You

Lesson Transcript
Instructor: Cathryn Jackson

Cat has taught a variety of subjects, including communications, mathematics, and technology. Cat has a master's degree in education and is currently working on her Ph.D.

Transversal lines are like puzzle pieces in geometry. Once you have the big picture of this puzzle, transversals can be fun problems to solve. In this lesson, we explore the many angles of transversal lines and review with a quiz.

What Is a Transversal?

A transversal is two parallel lines intersected by a third line at an angle. The third line is referred to as the transversal line. When this line happens, several angles are created. You can use these angles to find the measurements of other angles. When using transversals in geometry you can think about puzzle pieces fitting together.


The Eight Angles of a Transversal

There are eight different angles in a transversal. They are placed into five different categories. Knowing these angles can help you solve many geometric problems.

Supplementary Angles

Supplementary angles are pairs of angles that add up to 180 degrees. If you put two supplementary angle pieces together, you can draw a straight line across the top of the two angles. In essence, the two angles together make a half circle. Supplementary angles are not limited to transversals.

Supplementary Angles
Supplementary Angles

In this example, the supplementary angles are AB, CD, EF, GH and AC, BD, EG, FH.

Interior Angles

Interior angles are angles that are on the inside of the two parallel lines. In the example, the interior angles are angles C, D, E, and F.

Interior Angles of a Transversal
Interior Angles of a Transversal

Exterior Angles

Exterior angles are angles that are on the outside of the two parallel lines. In the example, the exterior angles are angles A, B, G, and H.

Exterior Angles of a Transversal caption=

Corresponding Angles

Corresponding angles are two angles that appear on the same side of the transversal line. One of the angles must be an interior angle and the other must be an exterior angle. Corresponding angles are congruent, meaning that they are equal measurements.

Corresponding Angles of a Transversal
Corresponding Angles of a Transversal

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create an account