The Substitution Method

Practice this lesson yourself on KhanAcademy.org right now:

Watch the next lesson:

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.)

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.

For free. For everyone. Forever. #YouCanLearnAnything

Subscribe to Khan Academy’s 8th grade channel:

Subscribe to Khan Academy:

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

I never listen to my teacher in class lmao, this why I’m looking up videos

Yeah I’m a junior in high school here

How you get 3

so all substitution have an answer

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

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

Nobody told me I could just -x when theres 2x I always tried to devide by 2 this makes my life 100% simpler

what did they use to record video

My problems are much more complicated than this

Thank you so much

Cool editting

easy money! I wish I can play game in class!

I don’t derstand where you got the 3 from

if you get rid of the “y” at the end of the problem solving then you do NOT get y = 3; you get 2 = 3. That makes absolutely no sense. if you get rid of y, you have to bring down the 2.

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

Please get a better microphone

Thks

i watched this 1million times and i still don’t get it

?…….

Now I know y math is so hard…..get it?