# 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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## 17 thoughts

1. Yaw says:

2:50 is it 2ax = – 4x or – 2ax = – 4x ?

2. Anjum Zeeshan says:

The only reason I still like math my teachers are o useless ily Khan academy

3. Aryaman Goel says:

So Easy lol

4. Healable Hades says:

Why can’t you just convert it to standard form, and then use the quadratic formula?

5. Julie Cramer says:

Thanks!

6. BEAST_GAMER says:

Hey really help with stuff that I am struggling with

7. Nationale Sozialistiche Deutsche Arbeiterpartei says:

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

8. Richie Mello says:

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

9. Arun Prathapan says:

Where does the +/- come from @4:10? Many thanks

10. Cj McKnight says:

THANK YOU!!!! This helped me study for my test

11. Xavier Lennard says:

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

12. Kennedi Lubale says:

8th grade algebra sucks. But you made me understand a lot more thank you

13. Eric Muiter says:

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.

14. Morgan McCracken says: