Solving Quadratic Equations By Completing The Square | Algebra II | Khan Academy

Solving Quadratic Equations by Completing the Square

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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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Solving Quadratic Equations By Completing The Square | Algebra II | Khan Academy

20 Replies to “Solving Quadratic Equations By Completing The Square | Algebra II | Khan Academy”

  1. How come you stuck a four in that gap instead of dragging the neg five there? Totally don’t understand this.

  2. so why is the “2ax” magically not negative since it has  negative sign infront of it? Can anyone explain please.

  3. This says algebra 2 . So I’ve been taking algebra 2 things in 8th grade… wow I’m so mad rn

  4. Hello, and thank you in advance if anybody responds. And peace to all. I am taking a union apprenticeship test tomorrow basis of which is basic algebra, and geometry. i.e. linear distance from fraction to decimal and vice versa. Add/Subtraction unlike terms. Factoring Quad equations and solving quad.following a given formula.
    As far as the geometry its radius, circumference, arc Lengths, parallel lines and transversals. Math was once effortless for me as i see it now in my girls 18,11,6.. Ya i know pray for me.. haha.

  5. at 5:20 why did (x-5)(x+1) get become x=5 and x=-1 and not x=-5 and x=1 like in the problem?

  6. Why was someone with a NAZI handle critiquing others for being unkind? I had to report him.

  7. Thank you so much! I knew how to complete the square already but when it got to the harder equations with negatives, fractions and whole number coefficients as the a value I started to struggle. I’ve been looking forever for a video that shows how to do hard problems but all the videos i found used very simple numbers and did awful jobs at explaining. Thank you so much this helped a lot!!! Please continue to make videos that incorporate hard and strange numbers so that viewers can actually see how mathematicians work their way around the large numbers and not just the basics.

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