# The Pythagorean Theorem Intro | Right Triangles And Trigonometry | Geometry | Khan Academy

Introduction to the Pythagorean Theorem

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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.

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The Pythagorean Theorem Intro | Right Triangles And Trigonometry | Geometry | Khan Academy

## 40 Replies to “The Pythagorean Theorem Intro | Right Triangles And Trigonometry | Geometry | Khan Academy”

You math good khan tank you I am joking but really thanks a lot dude better then my mathematics teacher who cannot shut the class up and teach effectively ffs

2. DPhilipp32 says:

I’m in school right know and or class has to watch thing😂

3. matthew prasanth says:

This guy talks. To much but he is still a good teacher

4. kebman says:

sqrt(108) = 10.3923048454 according to my calculator :p You are indeed correct in that it is a little over 6…..

5. ROG5 says:

Shouldn’t the variables be lowercase?

6. DUSTIN SUMMERS says:

I HATE FINALS AND EOC’S

tomorrow final exam maths offff

8. KynarethAzura says:

I’m taking my GED test on Monday……Idk how it will go but i did want to thank you because your videos have helped me with math tremendously! your voice is absolutely soothing and everything is explained perfectly ❤

9. Strayan 4ust1n says:

Quality Content my dude

10. Omar P says:

You make math sooooooo easy. THX

11. Dank banana 1 says:

y did u have another root for the last three at the end?

12. Ibmiti Bmiti says:

why did he minus 36 ?

13. Clay & Play ! says:

This is very easy, thanks!

14. Jaydee not JD says:

(teacher teaching PYTHAGOREAN THEOREM)

Me when learning this : WHAT!! IT’S SO BASIC!!

Me when during test : did our teacher teach this to us? I don’t know this!!

Thanks u teach way more better than school

Thanks u teach way more better than school Thanks a lot!!!!!!

17. sebastian cuello says:

where was Sal when I was in tenth geometry.

18. Mystical Raven says:

Came here bc we need to learn this for or science lesson…

19. Anonymous Anonymous says:

I wish I was high on pytoneuse

20. kaisootrash says:

Got it! Thanks.

21. Sullivan Nix says:

Thanks again Khan. You’ve saved me again

22. Samurai Tv. says:

Hi

23. dmexikan16 says:

Idk why I was thinking of math i feel like learning more math for some reason

24. AwesomeAfrin says:

Thank you soooo much for this video!

25. Macie Wilson says:

This made no sense toward the end

Thanks,you’re a better teacher than my teacher
(No offense to him though)

27. D Lovely says:

I did this problem. I understand the need to factor the answer out to six square roots of 3. But I divided 108 by 2 and got 54 because when you are dealing with square root, you are essentially dividing the final answer by two to get the square. I just feel like the other method was a little too drawn out.

28. HacK iOS says:

👍

29. Elizabeth Lee says:

Me and this guy are going to become best friends this school year lol #10thgrademath

30. Giovanni De Freitas says:

This guys awesome

31. Jacob Friddell says:

What program is he using

32. Ursh anabi says:

I still don’t understand how you got c. It magically became 5?

33. High-Marshal_Jaeger says:

With online learning like this it’s a wonder physical schools even exist, granted the schools are more for brainwashing then actually learning anything useful these days.

34. Chris Laukoter says:

thanks you saved my test results buy 15 points

35. Myles TheWeedPileSmoker says:

quick maths

36. risto austria says:

I was just taking a regular shower before hitting the bed when all of a sudden the word “Phytagorean theorem” pop in my head. So I had to refresh my memory and watch this. It’s one of the weirdest thing happen to me this year.

37. iamtheralwus says:

Apparently, Pythagoras’s father invented an angle too but it was the wrong angle.

38. Brunette Scribbles says:

I understood this 100 % But on my math test I have 45%. );c

39. Sunil Skanda says:

Suppose that we’ve a right angle triangle each in each quadrant of our cartesian coordinate system, and the hypotuni of each of those triangles is considered positive while our theorem here gives two possible solutions (positive and negative soln.). Why do we only take the positive solution ?

40. Natasja Price says:

I appreciate that these videos explain a concept before labeling. I learn better if I experience something and then label or categorize it.