# Complementary And Supplementary Angles | Angles And Intersecting Lines | Geometry | Khan Academy

Let’s add some tools to our geometry tool belt. Here’s a thorough explanation of complementary and supplementary angles, as well as definitions of adjacent and straight angles.

Practice this lesson yourself on KhanAcademy.org right now:

Watch the next lesson:

Missed the previous lesson?

Geometry on Khan Academy: We are surrounded by space. And that space contains lots of things. And these things have shapes. In geometry we are concerned with the nature of these shapes, how we define them, and what they teach us about the world at large–from math to architecture to biology to astronomy (and everything in between). Learning geometry is about more than just taking your medicine (“It’s good for you!”), it’s at the core of everything that exists–including you. Having said all that, some of the specific topics we’ll cover include angles, intersecting lines, right triangles, perimeter, area, volume, circles, triangles, quadrilaterals, analytic geometry, and geometric constructions. Wow. That’s a lot. To summarize: it’s difficult to imagine any area of math that is more widely used than geometry.

About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We’ve also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content.

Subscribe to Khan Academy’s Geometry channel:

Subscribe to Khan Academy:

## 39 thoughts

1. Tristan Meadows says:

Great

2. TheTrollz says:

Thanks, this helped alot

3. MooMoo Math and Science says:

Thanks for the video. I linked to your video in my video description.

4. Suvidh Pradhan says:

math is fun

5. shanty Rose says:

I don’t really like math but I am getting better at it☺😊

6. Danna Worrell says:

when he said DAB I dabbed

7. Cj Haskins says:

cool man thanks

8. Cj Haskins says:

cool man thanks

9. xxXSalty_Viper420Xxx says:

I love khan, its great for refreshing what you already know.

10. Abdullah Hassan says:

Thanks I never was able to understand complementary and supplementary

11. Vishrut Kannan says:

Thanx
(Cam Newton, Dab all day) LOL😋

12. AJS D says:

this video really helps me thanks

13. gamer zone 120 says:

you are smart man

14. gamer zone 120 says:

:]

15. D N says:

You really did add some tools to my belt:):):):):):):):):):):):):):):):):):):):D

16. Lua Walter says:

Thanx, now I kinda, sorta understand complementry angles

17. Kevin Coronel says:

Oooooooohhhhhhhhhhhhhhh now I get kind offf

18. SpicyDragon 45 says:

thx a lot

19. the chicken in the car and the car cant go says:

ty

20. Hugh Drew says:

yay geometry…………..wow……so……….cool………

21. Equilibrium Imbalance says:

Lol angle DAB, I’m surprised he didn’t realize what his angles make up in literacy.

22. Equilibrium Imbalance says:

This guy is so good at Articulating, it’s pretty cool to have skills like that.

23. CrewGodz Knighters says:

Are you smarter than Siri

24. Anna Boyden says:

dab

25. Mazin says:

I love how you make things seem over complicated and do unnecessary steps while trying to explain that the angle equaled “90 degrees”.

26. Rokhsana Poly says:

nice video helped me in exam

27. Aaron Chew says:

Lol did anyone notice that he spelled supplementary incorrectly on 7:03

28. you mad lol says:

this didn’t help with any of my homework (using the complimentary angle theorem) wish you would of showed some actual examples of problems we might see, what you explained / showed was extremely dumbed down and irrelevant to problems we face in the classroom

29. Tima Pustovit says:

Revising for maths.
This really helps!!!

30. Adriane De Guzman says:

31. Chris Ramlochan says:

Nice video👍👍

32. levert. GOMEL lewis. says:

angles

33. Miguel Santos says:

HelpedMe in my Quarterly Exams Thanks!

34. Brett Rhines says:

angle D A B

35. Lauren Ginocchio says:

Hey future 7th graders!! SHoutout to Ms. Galvin

36. seth says:

FUCK YOOU YOU GIT ME AN F

37. Adriana M says:

great video helped me alot! 🙂

38. Nabeela ali says:

this is so hard to understand should have gome slower and explained proprely so hard to inderstand god!!!!

39. Nabeela ali says:

*understand