Completing the square to write equation in standard form of a circle | Algebra II | Khan Academy

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Algebra II on Khan Academy: Your studies in algebra 1 have built a solid foundation from which you can explore linear equations, inequalities, and functions. In algebra 2 we build upon that foundation and not only extend our knowledge of algebra 1, but slowly become capable of tackling the BIG questions of the universe. We'll again touch on systems of equations, inequalities, and functions...but we'll also address exponential and logarithmic functions, logarithms, imaginary and complex numbers, conic sections, and matrices. Don't let these big words intimidate you. We're on this journey with you!

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[chickenzwings]

Khan Academy: The Cure to the common shitty teacher 

[kko]

Thanks so much for the video.. have a quiz tomorrow, and my teacher barely covered this

[pyronic]

omg thanks dude you are so awesome... my instructor sort of just skimmed over this and i have a test tomorrow and you probably just saved my sorry but... Keep up the awesome work man!!!

[Heywood_]

Thank you, thank you, thank you! So much help!

[diegoramirez]

Thank you so much! By far the best video.

[sohaibahmed]

i would've just added 17 for the first step to make things easier

[rbthesunsetloner]

Thanks Sal. Also props for being bengali too. :-)

[techno_tuna]

Thank you so much for this, been a little out of it in class and couldnt keep up recently but you made it so clear, damn math book didnt help nearly as much as this video.

[nonsithsatia]

Let's check our answer:
"We got it right."
Totes badass.

[qiannivan]

I wish you haven't used number 4 for example because doubling half of 4 is the same as adding it, the special number of 2 is making no sense.

[galacticcow]

Khan you are my late night Red bull fueled savior.

[gomimi]

what if x^2 and y^2 have different coefficients for example 2x^2 and 3y^2??

[ekrem]

What if there is no coefficient for x; x^2+y^2-14y-51=0

[moptfor]

do it when a and b are not one like this a(x+2)^2+b(y-2)^2=whatever

[heanlygaming]

what would be the final answer if the value of the r² cant be squared for example r² = 45

[zionj]

I think I'm having a synesthetic reaction from ~3:07 to ~3:20. I think Sal saying certain sounds is making me have a faint taste of spicy licorice.