PreCalculus - Algebra Fundamental Review (17 of 80) Sol Quadratic Eqns: Completing the Square

In this video I will use the completing the square method for factoring x^2+5x+8=0.

[shrimpkins]

Hi, loving all your videos! Quick question: When you take the √ of both sides at the end of the process, why is the right side qualified with ±, instead of just + ?

[jane]

Hello, I was wondering how you went from X^2+5x+(5/2)^2 to (x+(5/2))^2? Where did the 5x go?

[brewertonpaul]

Sir, @ 1:04 in example #1 and @ 3:34 in example #2, you simplify the expressions and omit the middle term. How can they just dissappear?

[heartsofgoldenrod]

Can you complete the square with a negative bx?

[hamids]

i dont understand why you would use this method. could you explain please?

Thank you

[pepecohetes]

Michel: will you get the same results for the 2nd equation just using the quadratic formula?

[JossinJax]

Sir, I'm really trying to follow you here, but when I square (x+5/2)^2 I get =x^2+5x+25/4. I feel like I'm overlooking something.