Completing the square for vertex form | Quadratic equations | Algebra I | Khan Academy

Completing the Square 3

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Algebra I on Khan Academy: Algebra is the language through which we describe patterns. Think of it as a shorthand, of sorts. As opposed to having to do something over and over again, algebra gives you a simple way to express that repetitive process. It's also seen as a "gatekeeper" subject. Once you achieve an understanding of algebra, the higher-level math subjects become accessible to you. Without it, it's impossible to move forward. It's used by people with lots of different jobs, like carpentry, engineering, and fashion design. In these tutorials, we'll cover a lot of ground. Some of the topics include linear equations, linear inequalities, linear functions, systems of equations, factoring expressions, quadratic expressions, exponents, functions, and ratios.

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[matthewlatinis]

Learned more in 6 mins than 3 weeks of class

[godofaztecs]

Harvard: What high school did you go to
Me: Khan Academy


Harvard: It our honor to select you

[chaostheory]

Was anyone else's mind blown when he just added 16 and then subtracted 16, just so he can get a perfect square? This is sooo useful when you have an equation that does not have a perfect square.

[bandit]

Thanks! I’ve been prepping for my Algebra I regent and I realized I didn’t remember how to do this, this video helped me brush up on it. Very informative and explains it well

[vishaanthmk]

thank you so much for this video, it is really good and informative

[sinistril]

So... my teacher's been doing it wrong all term, I've been doing it correctly. I even asked her about it and she said I was wrong. Checked this and ran the equation through Symbolab to verify lol. The question is... my final is tomorrow, do I do it correctly or wrong haha

[TheSheepster]

Seriously, THANK YOU! This really helped me understand what my teacher quickly taught about in class, all the pieces are clicked together.

[malinamorales]

Video we didn't wanna watch but the video we desperately needed

[whisper]

I would use h and k instead of b and c because in completing the square ax^2+bx+c the b and c don’t equal b and c in vertex form

[kelseysandau]

SAVING MY LIFE DURING ISOLATION THANK U

[anovah]

thank you for making me feel like a gangster

[ZR_R]

The reason I'm watching this in 7th grade is beyond me.

[afokujabi]

You are best...your video helped me alot. Thanks

[ComtrollerReviews]

Reminds me of how useless all of this is

[okas]

Khan academy is the hero we don’t deserve but the hero we need (especially in quarantine)

[eathus]

Thank you, this video was very helpful. Was trying to figure this out for hours until I found this video thanks.

[thepineappleswilldominate]

THANK YOU SO MUCH I was gone for two days and I have an important test tmrw

[anicamya]

alr, im gonna mind blown my teacher after showing my solution lol
this is really helpful and understandable than a 1hr and 30mins class

[avak]

my math test is in about an hour and hopefully this will help me not fail

[CalfordMath]

It would be nice to see an example where the "a" value isn't factorable from the constant term, as this is more commonly the case students see, where you have to partially factor "a" from the variable terms and leave the constant out altogether until the end.