Solving quadratic equations by completing the square | Algebra II | Khan Academy

Solving Quadratic Equations by Completing the Square

Missed the previous lesson?

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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Me in 9th grade= What is this witchcraft?
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Do people appreciate the genius of this method, and how everything just works out?

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thank you khan academy!! my girlfriend and i couldn’t cook pizza and we couldn’t complete the square either!! BUT YOU HELPED US SOLVE ONE OF THOSE PROBLEMS :))

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I have ADHD and yet still I've learned more from these guys in this video than I have in algebra class throughout the whole unit on quadratic equations

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