Introduction to rational and irrational numbers | Algebra I | Khan Academy

Introduction to rational and irrational numbers | Algebra I | Khan Academy

Introduction to rational and irrational numbers | Algebra I | Khan Academy

Learn what rational and irrational numbers are and how to tell them apart.

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Algebra I on Khan Academy: Algebra is the language through which we describe patterns. Think of it as a shorthand, of sorts. As opposed to having to do something over and over again, algebra gives you a simple way to express that repetitive process. It’s also seen as a “gatekeeper” subject. Once you achieve an understanding of algebra, the higher-level math subjects become accessible to you. Without it, it’s impossible to move forward. It’s used by people with lots of different jobs, like carpentry, engineering, and fashion design. In these tutorials, we’ll cover a lot of ground. Some of the topics include linear equations, linear inequalities, linear functions, systems of equations, factoring expressions, quadratic expressions, exponents, functions, and ratios.

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.

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40 Responses to “Introduction to rational and irrational numbers | Algebra I | Khan Academy”

  1. EZ says:

    POV: you have a test tomorrow and you ARE NOT READY

  2. Ananya Tiwari says:

    watching in 2X speed

    while u r the best teacher

  3. Radha Talluru says:

    your introduction is good but your explanation is lame

  4. Keerthana S says:

    Is 3.14 is rational or irrational

  5. Lolao Pajaks says:

    Thank you

  6. AYAN AKIF says:

    Comment section not dead even after 7 years

  7. Learn at Ease Divyanka Sinha says:

    Target is 100

  8. Gabe Lanning says:

    POV. End of year test are coming up and you haven’t learned anything😂

  9. Cherry Lucid says:

    He has such a nice voice

  10. Huma Faisal says:


  11. Lonely Potato says:

    But Pi can be represented as 22/7 which is ratio of two integers. You included Pi in irrational why

  12. Komal says:

    Thank you Sir

  13. Aash says:

    This sounds like Ranboo

  14. Ayleen Reyes says:

    I don't what I would do if sal didn't exist

  15. Manu Y says:


  16. coldmayo says:

    this made no sense….can anyone link me to a video that actually makes sense

  17. K a r e n says:

    me learning all of this before the exam tomorrow at 2am : 👁️👄👁️📝

  18. Shaik Gaffar says:

    😅😅 very late

  19. Dystopic says:

    Question: Is the gravtional constant g considered irrational?

  20. Saad Baig says:

    rattttional number
    rrrattionnal number

  21. Panashe S says:

    i hate the name khan cause my teachers name is khan and and i hate her

  22. anna says:

    i’m watching this from my 8th grade math!

  23. HaCkEr says:

    our teacher was teaching us for a month just for this and no 1 learned it
    but now i fully understanded it in 5 minutes

    i wish i could pay some thing for u

  24. Zethu Mpanza says:

    Is square root of 9 is rational or irrational or neither…im in grade 9

  25. TB7 says:

    Sal is the man.

  26. Ankit Mitra YT says:

    Who's watching this in 2021!

  27. Mars_2500 says:

    Rip you

  28. Lucas bender says:

    what about /3

  29. ゆきyuki says:

    This is not boring like my teacher

  30. Josselyn Espinales says:

    I didn't understood 🙁

  31. Amalya Monroe says:

    I failed a test and now I have to watch all of your videos thx tho

  32. Saranya Saranya says:

    thx i was struggling with thisf

  33. Genesis Casey says:

    So -1.34 repeating is rational?

  34. not me says:

    Is this DJ Vlad???

  35. Rashdan Harsh says:

    You say between rational no.1 and rational no.2 there will always be an irrational number, but take 1 and 3 for example. Isnt 2 a rational number?

  36. Maryam Khan says:

    3:14 hi

  37. Shabib Khan says:

    It's the best

  38. Anwell 09 says:

    My teacher literally just said "This is a rational number. Now think of a problem with one" . THANK YOU


    that's mr -s. Mr-s we learning that, too. thx for helping us

  40. astram says:

    my math teacher just puts these kinds of videos and goes away

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