How to rationalize a denominator | Exponent expressions and equations | Algebra I | Khan Academy

How to Rationalize a Denominator

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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.

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[angelarose]

"why do we care, why do we have to rationalize the denominator?" because it's going to be on my test :(

[rakithawijarathna]

This man a living legend he’s helped so many people, Teachers aim to be you. I cannot thank you enough I’m taking high school dash one and this is beyond helpful. I honestly wish you were a teacher at my school.//Many thanks keep it up👍🏽

[hernaniCH]

when i was still in highschool, i thought this is gonna be useless..

now im in college, ahahahahahaha back to basics

Thanks you good sir

[joshciruli]

im only 13 and my pop is trying to get me ahead sometimes i cant understands the way he teaches me but you gave me a clear explanation thanks for putting in your time and effort

[janehervilla]

Yep, pretty sure gonna fail my exams now

[FreakigesSternchen]

oh my god thank you so much we're doing that in school right now and i missed a few days and no one bothered to explain it to me so thank you for making this!!

[ericmacisaac]

Lamo now that we are doing online schooling do to the quarantine, my teacher just leaves a bunch of links to your videos to teach us

[SS-hnue]

Well I wish you were my teacher. My teacher doesn’t teach, we have to teach ourselves and she expects us to know how to do everything

[scrawnic]

I have learnt all of my math from you Sal Khan. You are my true teacher. You have helped me rise in math to be one of the top mathematicians in my school. Thank you so much for your help.❤❤❤

[akshar]

You sir, are one of the best teachers I have ever learnt from, Thank You.
I just don't understand why rationalization is done.

[SintOfMrcyCOC]

I'm so done! This makes no sense in my classroom

[fgdtryrt]

Thank you much. I can't tell you how many time your videos and great explanation skills have saved me!

[waynerd]

this would have prevented a fist fight the last time my friend and I built a rocket

[Swetlana]

Again perfect timing!!!!
We are doing it class now!
I am so happy!

[AcornFox]

Thank you so much, especially for giving actual reasons for doing this. The rocket science example flicked a switch in my head. When I was in high school no teacher could ever give a practical reason for anything other than "It's on the test, " so I thought it was kind of stupid. Now that I am going back to college (after seven years) I love math, and this makes sense to me. Standards are crucial for collaboration: brilliant.

[pragneshsolanki]

Math (in primary) - Piece of cake :)
Math (in secondary) - No comments :(

[marwinsteiner]

Posted 11 years ago and still gold! :)

[Denelle]

I'm in my senior finals, I can't remember the last time we had done this in school, but thanks you sir, I'm gonna be okay

[Haley]

THANK YOU! so helpful. going to start using these videos to study!

[RIPTIDE_]

Thank you sir. In 2 days there is my math exam and still I didn't know how to ratlionize until I saw your video. Thank you once again.