Infinite solutions to systems | Systems of equations and inequalities | Algebra II | Khan Academy

Consistent, but dependent systems of equations

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[Jaytheforth]

This kingdom has an awful lot of convenient problems.

[ewertooo]

Sal seriously, I dont know how its possible for u to have another talent, but your drawings are so well defined and show such understanding of shape and proportions!

Please do a series on drawing or something where u illustrate more. U might be the Indian reincarnation of da Vinci :3

[CoolDude]

I have done loads of matrices but I just watch for the funny story about the troll and the bird.

[IAmTheNoodleFish]

Sal would probably be the court wizard in this kingdom.

[mxlexrd]

You should give an example where the system is consistent and gives 1 solution but that solution is nonsensical or forbidden by a further constraint such as a > 0 and b > 0.

[mamadetaslimtorabally]

Great way of explaining how there arises an infinite number of solutions to a system of equations. Thank you Khan.

[xzxburnedxzx]

Great Job Man, you have helped me through all of my school

[azgh]

I'm a freshman and I'm taking algebra-2 (an eleventh grade math class) there is still hope for me to become the next sal khan :)

[jimsavage]

Wouldn't negative 2a go to the left of the b axis?

[I-did-not-ask-for-a-handle]

Thus was the first thing I thought but I thought he was going to solve it...

[dennishayslip]

well done. within the time frame. dennis hayslip

[randomguy]

Cool. We care SO much about Mitt Romney, don't we? ;D

[SWEATDelta]

How long do you think it takes to make that art? 😳

[Roamer]

Tell the King people are extra hungry because they had a hard crop year and see what the bird says.

[rhoadess]

I can't believe it, Mitt Rommny called me himself, but he got my name wrong! He called me Russel. Yes, for two unknowns you need two different equation with the same variables. Let n be number of unknowns, then to solve for each variable, you need to setup n number of equations.

[pepitobenegas]

I still don't understand why we have to multiply by -3 what happens if I have other numbers? My book says to multiply by -2 but doesn't give a reason. What should I do?

[randomguy]

Because that's not racist at all...

[rhoadess]

Well if he becomes president we might care about him, but since he called me I have also had calls from Clint Estwood, and Ann Romney, among others. I am not, in any way endorsing Romney, nor am I endorsing Obama. Regarding this video, I might mention that just because we may have the same number of unique equations as unknowns, we are not guaranteed a unique solution to each unknown. An example might be a line passing through a sin wave.