solving systems of equations with cramer's rule (KristaKingMath)

The three most common methods for solving a system of linear equations are elimination, substitution, and graphing. In this video we'll learn how to use the less common method, Cramer's rule, to solve the system.

Cramer's rule involves finding the determinants of the coefficient matrix, and the determinants of matrices for each variable.

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Hi, I’m Krista! I make math courses to keep you from banging your head against the wall. ;)

Math class was always so frustrating for me. I’d go to a class, spend hours on homework, and three days later have an “Ah-ha!” moment about how the problems worked that could have slashed my homework time in half. I’d think, “WHY didn’t my teacher just tell me this in the first place?!”

[chad]

Yet again another 5 minute video that explains a concept better than my professor did in 2 hours.

[davidb]

Wow, this was so much simpler than what my teacher explained. THANK YOU.

[ahmedalaraby]

Your life saver there is some place in heaven for good math teachers

[TheDominion]

Thanks for the video. I've used the elimination method to solve these, but I think I'll utilize the Cramer's Rule. Your explanation is very practical.

[luguzman]

THANK YOU SO MUCH FOR EXPLAINING IT SO CLEARLY!! I have a quiz on this tomorrow and I didn't understand the 45 minute lecture my teacher did on this until I saw this 5 minute video.

[Jlynnka]

Thank you so much!! You helped me and my friend learn cramer's rule sooo easily, and saved our grades!!

[ThePinoyMamba]

Well done Krista.. I forgot about this one

[pamiimiap]

This was amazing! You explained it so easily! <3

[_oig]

Is it weird that I use cramers rule to balance chemical equations. Awesome video btw! =D

[kishoreprakash]

at 3:40 you messed up and wrote negative 28 but you said positive 28

[c.james]

Cramers rule is much easier and quicker to use than matrix inversion to solve systems of equations, especially with 3 variables (3x3 matrices) but sadly my linear algebra course at university did not teach it (im doing Physics not maths)!

[lukamorchiladze]

epic, way lot easier than Substitution method or Elimination method, thanks

[Foxylinsky]

What if I get a decimal answer when I do the x= Dx
D

[shafiqahmed]

your 14 looks like 19 and if it was 19. it would have changed the whole thing :P