What are variables, expressions, and equations? | Introduction to algebra | Algebra I | Khan Academy

Learn what variables, expressions, and equations really are.

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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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[greengrain]

I'm almost 26 years old and working an overnight security guard job and wanting to do more with my life. I didn't fit in with how things were taught when I was in school, and dropped out of high school. I was homeschooled from 6th to 8th grade so when I came back to the public school district they threw me into algebra 1, and unsurprisingly, I failed it 3 times. Now here I am again, learning on my terms, and so thankful that this free resource exists. Like Galileo said, "Mathematics is the language with which God wrote the Universe." It belongs to all of us and I'm proud of anyone else here trying to learn even if it isn't intuitive to them. Keep going!

[dfvywhy]

Got a 92% on my Math Test this week because of this video I studied 10 minutes before the test too. 👍👍👍👍 thanks

[LatiloveOmg]

Why do math teachers even bother teaching? Just show us a few videos of Khan academy.

[soupbowl]

Wow somehow you are better than my actual teacher in a 6 minute video

[iitechx-tv]

I don’t understand anything in school, but this 6 minute video saved my grades, thanks!

[caolijuan]

my son is 10 and has currently know most of algebra complicated and basic, we want him to watch your algebra vids from basic to complicated so he doesn't forget this very useful math

[xjamine.dx]

you teach me better then my math teacher ... thanks sooo much  

[williamharding]

my teacher already taught me this; but i still need to know this

[DesperateKnowledge]

I love it, straight to the point. without flapping his gums. thanks alot

[buRnthastuff]

I have just found your channel and you're a very good teacher...
Even though this topic is not what I find very hard as I'm already more advance.
I look forward seeing the subjects I'm seeing in my Maths class right now.
Thank you very much for the lessons, they are greatly appreciated and I think I'm speaking for everyone else here :)

[tacoMIW]

Man how is he so good. I used to hate algebra because I didn’t understand it but now I love algebra

[tnguyko]

Great vid. Wish there weren't any negative integers for the low ability students.

[oscarjrdepamaylo]

Hi Sir, I just want to point out at 05:40, -2³ is not the same as -2 * -2 * -2. Since it was not on parenthesis, just so not to confuse others. Thanks for being my teacher. Please keep it up!

[meowmaster]

not me using this playlist to straight up fall asleep to-

oh i am
this guy's voice is very nice

[ayyahsaleh]

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[rahmaahmed]

way more helpful than my maths teacher

[lucyweaver]

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[Ducksandcatsarebeautiful-]

Teachers take 7 hours to teach us something but khan academy videos take 7 minutes

[mmiralooplets]

These videos are fun and very helpful! Thank you for making them!

[DanielleAssadourian]

so i have a question; if you had, for example,  
x + y + z = 5 but you weren't given the values of any of the variables, what would you do?