How to use the quadratic formula | Polynomial and rational functions | Algebra II | Khan Academy

Introduction to using the quadratic formula.

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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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[AAwesomePantss]

I learn more from you than my math teacher

[katsudonewithyoass]

Throughout the years this channel has saved my butt so many times. I hope whoever makes these videos is living a prosperous and happy life 😌

[abelalvarado]

Students: Can we learn how to do taxes?
The Education System: Screams in quadratic formula

[henrywiley]

In class we spend weeks on a subject. I just learned what I needed to in 15 minutes for my test tomorrow

[iconsumekneecaps]

Who else is staying up at 1 AM watching this and trying to get your homework done in a panic??? 😂

[diluted_potato]

You're amazing, before this I didn't understand quadratics one bit. Thank you so much!

[junyang]

This teaches you more than a zoom meeting ever will

[blickbeared]

Sir I believe that you may have saved my grades, you indirectly told me what I was doing wrong.

[CRSBERaif]

For the second example, I spent like 15 minutes trying to figure out why my calculator was saying math error until I watched the rest of the video and it doesn't have a real solution....

[benr]

I want to be a math teacher, but I needed this refresher. I always mess up the formula because I didn’t learn it by heart. I imagine 99% of people struggling in math just are missing some basic building block like this, and I’m part of that 99%. Thank you again for making math less mysterious and clearly wonderful. I’m arguably more proud of my energy points score than any other academic accomplishment in my life lol.

[onikabogdan]

I've watched about a million of your videos because I came into Algebra in the middle of the semester and now I have the EOCs and I was freaking out that I didn't know any of it. THANK YOU THANK YOU THANK YOU.. I have been saved and now I don't have to worry about failing 8th grade!!!

[kappaisreal]

At 8th grade (where I am right now), I have been studying hard in school and at Math. I challenged myself to get at least 85%/100% of the answers when having a test without watching some tutorials and it strucked me that I can do it without any help of others



I want you to believe in yourself, you can be great by studying hard and please do not let your guard down

[bashkillszombies]

Of all the math I've learned I've used none of it in the real world. :(

[JesusIsCometh]

5:17 you can hear gears grinding together in his brain . . .

[heidiborjgmanschmange]

I think I hurt my brain. That's quite a formula

[flesh]

i swear he uses magic to teach people through a video

[shreyan]

This formula was discovered by an Indian mathematician Sreedharacharya. I'm so proud to be born in the same country as this mathematical genius.

[innversion]

I'm Rick Harrison, and this is my pawn shop. I work here with my old man and my son, Big Hoss. Everything in here has a story and a price. One thing I've learned after 23 years, you never know what is going to come through that door

[tahminaislam]

Why would I need Algebra or these in my life? I really don't want to have to do anything with maths.

[logankaiser]

I'm in a duke program for advanced 7th graders and we are doing an SAT. Before this I didn't understand this. Now I have NATIONAL HONORS for my score of 740