The substitution method | Systems of equations | 8th grade | Khan Academy

The Substitution Method

Missed the previous lesson?

8th grade on Khan Academy: 8th grade is all about tackling the meat of algebra and getting exposure to some of the foundational concepts in geometry. If you get this stuff (and you should because you're incredibly persistent), the rest of your life will be easy. Okay, maybe not your whole life, but at least your mathematical life. Seriously, if you really get the equations and functions stuff we cover here, most of high school will feel intuitive, even relaxing. (Content was selected for this grade level based on a typical curriculum in the United States.)

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[duster]

You teach soooo much better than my teacher!! My teacher just gives us worksheets for a week and expects us to understand and i learned more from a 4 minute video than in a week in her class

[danielyourestillachad]

i honestly feel like an idiot for being the only one in class who doesn't get this

[Noobelli]

Thanks. My teacher sucks at explaining and a 4 minute free video helped me better than SCHOOL ITSELF.

[edonkulation_hd]

My teacher shows us how to do it ONE time then examples for a few days then new subject.

[ducktapeeverything]

Yeah I'm a junior in high school here

[crybabyenby]

I’m in 8th grade learning sophomore math😭 Thank you I finally understand it now

[valeriealondradelgadomacei]

this didn't help that much, you should add different types of problem to give the viewers a clue of how to solve them in my opinion

[JJuribe]

I've been learning this for a month; this is the first time it's made sense in a reasonable way. thank you.

[lolabisk]

When your teacher doesn't even teach you for your exam and tells you to go on videos instead

[lyannastarkeys]

i understand this more than what my teacher discusses, thanks!

[littleWOLFinME]

THANK YOU

I was stuck trying to do my math homework, and this video beautifully explained everything so thaaaank you so much<3

[PoseidonodiesoP]

Simple questions.. no one ever goes over the hard ones. Awesome

[masterman]

... Now i know my teacher i terrible. You make it look so easy.

[noursvsp_]

thank you so much for this. substitution has always been so difficult for me to understand and i have a test tomorrow, but after i watched this it’s now extremely easy. thank you so much, you’re saving my math gradesss

[evelynsnowden]

When are we going to use this in real  like Fr

[toriabear]

have a quiz on this tomorrow along with the elimination and graphing methods, this helped me a lot!

[TheTwinkeman]

God ...when my teacher explained it i could not understand 1 word, but you guys, i just wanna say thanks for this dudes. y'all ROCK!!!

[pacaura]

Bless you. I have a very important math exam coming up, and i was really stressed about this. I decided to look at these videos, and less than 2 vides later i feel like i understand everything.

[brandon]

How does this man do this with a mouse

[Joseph-sgjz]

I learned more in a 4 minute video than in a week of class. My math teacher is Khan.