Solving systems of equations by elimination | Algebra Basics | Khan Academy

Solving Systems of Equations by Elimination. Created by Sal Khan.

Algebra basics on Khan Academy: Topics covered in a traditional college level introductory macroeconomics course

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[Goldan]

Anyone else feels like they can actually get to like math if only they can understand it?

[jinglearesko]

Is anybody just not gonna talk about this guy's right to be one of the best teachers out there? He actually explains it in a way that makes sense.

[disgusting]

IRL They tell you the cost of the candy bar lmao

[TekHelpDotorg]

You know most teachers go in teaching this but don't explain how come we can add two equations. And you have this constant question in your mind. Well you have answered that question. Thank You!

[aygklo]

"blah blah blah blah blah and don't forget to blahhhh~ blahh blah blah *You're gonna fail your test on friday* blah blah and blah" Is all I heard.

[baileybrown]

I have my exam tomorrow and i still dont know how to do anything

[holyfrack]

I don’t understand why this must exist. Why do we have to know elimination? Why can’t we just learn substitution, because apparently you will still have to use substitution if you do elimination. This learning system is RIGGED!

[jayparmar]

My teacher should just show us your videos during class, I'd learn so much more in so little time. You've changed the world Sal!

[SkillUpMobileGaming]

GOD DANG IT... He's so Organised in his videos! He is mote organised than ANY TEACHER I HAVE EVER SEEN plus he is using his mouse to write instead of Paper and Pencil. This guy explains stuff in detail VS. my Teacher who teaches methods with no explanations. My teacher taught this lesson without ever explaining WHY she is doing it! Khan Accademy... it has changed MILLIONS OF LIVES by teaching without price. This man is pure Genius! Please like this comment if you agree... 😔👹😔

[mykinfair]

"Fruit ROOLLL-UPP" @6:50 makes me lmao

[James-mcws]

HELP!! I TOOK HIS ADVICE AND NOW I'M STUCK IN AN INFINITE LOOP OF ADDING AND SUBTRACTING

[billhable]

This is so complicated....and I still don't get it

[mccarthyroderick]

It’s crazy I feel when people explain math! I feel they skip why they are doing certain things to the problems, they just write things in as if you know why they are doing the steps! I feel a great math teacher explains in detail why her or she is writing anything in a problem!

[jerfersonmatos]

the x was easier to find, just think:

IF NADIA BOUGHT 3 CANDY BARS AND "4" FRUIT ROLLS FOR 2.84
AND PETER ALSO BOUGHT 3 CANDY BARS BUT "1" FRUIT ROLL FOR 1.79 we can assume that (2.84 - 1.79) is equal to 3 fruit rolls.

[Daisyeexo]

I have a test tomorrow morning and I don’t understand any of this so please wish me good luck 😔😂🙇🏽‍♀️

[benedictcuello]

When he said 2.5, I know that I’m going to fail my Math class

[lawrencegoldman]

"Hey Sal, but wait..." You're the best, dude.

[Nya-the.one.and.only-]

thank you so much. i was gone when we learned this in school and the teacher never got around to expalin this to me. this makes so much sense

[CoachAbdullah]

Wow made it so much easier to understand

[sarahsheikh]

How do we know whether to add or subtract the equations?