Math Algebra II
posted by Christina .
x^24x+12=0 Complete the square to solve for x.
Okay I know how to do up to here:
(4/2)^2 12=x^24x(4/2)^2
212= x^24x+2
10= DO I FACTOR IT?

x^2  4x = 12
x^2  4x + 4 = 12 + 4
(x2)^2 = 8
x2 = ± √8 , but √8 = 2√2 √1 = 2i√2
x = 2 ± 2i√2 
Easist way always is to go and get the roots:
(b + sqrt(b^2  4ac)) / 2a

x^2 4x +12 = 0
a= 1, b=4 c = 12
((4) + sqrt(16  4*12)) / 2

(4 + sqrt(32))/2

4 + sqrt(i^2 * 16 *2))/2

note : i^2 = 1
(4 + i 4 sqrt(2))/2

Ans:
2+ 2i sqrt(2)

are the two roots
Hope this helps Christine!
Respond to this Question
Similar Questions

algrebra 2
it is called completing the square here is the equation 4x^24x+1=9 if anyone can help me please do okay i really need ot understand this 4x^24x+1=9 Move the numbers to the other side. 4x^2 4x = 91 4x^2 4x = 8 Now factor out 4 … 
Algebra I
The distance an object falls is directly propotional to the square of the time it has been falling. Afterr 6 seconds it has fallen 1296 feet. How long will it take to fall 2304 feet? 
Pre Cal
Ooops! I wrote it wrong, here's the problem: if x varies directly as y^2, inversely as z, and inversely as the square root of w, what happens to x when y is multiplied by 3, z is doubled, and w is quadrupled? 
math,help,algebra I
I need help can someone help me get unstuck and let me know if i am correct.thank you. solve by completing the square. 4x^2+2x3=0 this is what i am doing: i used the quadratic equation. so where i am is in this step: x = (2 (+) … 
algebra
solve the polynomial y=2x^24x+1 For Further Reading algebra  Reiny, Thursday, May 17, 2007 at 10:34pm I am sure neither your text nor your teacher asked you to "solve the polynomial y=2x^24x+1 " are you graphing the function, or … 
Algebra
My homework is to solve by completing the square. But how can you complete the square on this problem? 
Algebra
Complete the square for the binomial. Then factor the resulting perfect square trinomial. x^2 2/11X 
Algebra
Complete the square for the binomial. Then factor the resulting perfect square trinomial. x^2 2/11X 
Math (Quadratics)
3. Solve for x in 8x^2 + 2x  4 = 0 I have tried factoring, taking out a GCF then factoring, completing the square, and got a bunch of wrong answers. I thought we were supposed to complete the square, so maybe I'm just doing that wrong. … 
Complete the Square
My teacher wants me to make 5 hard complete the square questions and solve them in front of her to get a %5 bonus mark. Can anyone give me 5 really hard complete the square questions?