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

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

Practice this lesson yourself on KhanAcademy.org right now:

https://www.khanacademy.org/math/algebra/rational-and-irrational-numbers/irrational-numbers/e/recognizing-rational-and-irrational-numbers?utm_source=YT&utm_medium=Desc&utm_campaign=AlgebraI

Watch the next lesson: https://www.khanacademy.org/math/algebra/rational-and-irrational-numbers/irrational-numbers/v/proof-that-square-root-of-2-is-irrational?utm_source=YT&utm_medium=Desc&utm_campaign=AlgebraI

Missed the previous lesson?

https://www.khanacademy.org/math/algebra/exponent-equations/radical_equations/v/applying-radical-equations-3?utm_source=YT&utm_medium=Desc&utm_campaign=AlgebraI

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.

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algebra tutors,[vid_tags]

algebratutors.org

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

watching in 2X speed

while u r the best teacher

your introduction is good but your explanation is lame

Is 3.14 is rational or irrational

Thank you

Comment section not dead even after 7 years

Target is 100

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

He has such a nice voice

Awlllaaaa

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

Thank you Sir

This sounds like Ranboo

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

I LOVE UR LESSONS SAL THANK YOUUUU

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

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

😅😅 very late

Question: Is the gravtional constant g considered irrational?

rattttional number

rrrattionnal number

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

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

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

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

Sal is the man.

Who's watching this in 2021!

4:00

Rip you

what about /3

This is not boring like my teacher

I didn't understood 🙁

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

thx i was struggling with thisf

l

l

So -1.34 repeating is rational?

Is this DJ Vlad???

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?

3:14 hi

It's the best

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

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