# Solving Linear Systems By Substitution | Algebra Basics | Khan Academy

Solving Linear Systems by Substitution. Created by Sal Khan.

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

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## 22 thoughts

1. The Whale Burgers says:

This helps so much. Thank you khan academy!!!

2. Aaron Escoto says:

raja

3. Antonia Meneghini says:

I need to know how to do this with the equation written in slope-intercept form

4. Ana argueta says:

thank the Lord this helped a lot

5. Beatriz Valdes says:

it’s 2 in the morning and I’m studying last minute for a test I have first period…

6. Night Evolved says:

what do you do if you have 9y=-18

7. john tindell says:

thank you so much, it was immensely helpful

8. Elizabeth Stapels says:

Thank you so much!!!

9. Josh Hend says:

help

my problem had the 2 variables on different sides

11. Final Boss says:

why cant we just learn this directly instead of going througj graphing before this? its so annoying

12. assassinwolf gaming says:

I dont get it, its probably not you but someone please help. I have a quiz on this tommorow

13. Mac says:

simplest video on this on youtube thank you so much!!!!

14. mr muers says:

on the step 27-6y+5y=20
how did you get -y?
wouldnt it be 11y? im confused

15. Omnipotent WaffleGod says:

Why cant my teacher just show these videos! It helped so much.

16. Zeb Arnwine says:

ninja

17. Ugo Ilodigwe says:

He multiplied by -1 because variables can never be negative for those wondering

18. _Eternity Studios_ says:

why do i have to learn this if I’ll never use it in real life

19. SDEpiclord says:

I wish he was my math teacher

20. Dhwani says:

I HATE MATH

21. 7 bratayley kids says:

i dont understand a sentence that came out of his mouth

22. porky guy says:

For some reason it’s funny to me that he refers to the x=9-2y as “this thing” 😛 2:00